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Guide: Running a Business in Germany

Everything a craftsman needs to know about taxes, bookkeeping, and regulations — step by step.

Table of Contents

Before you take your first job, you need to properly register your business. Here are the necessary steps.

1.1 Choosing a legal form

Germany offers several legal forms (Einzelunternehmen, GbR, GmbH, UG). Most craftsmen choose one of two:

  • Einzelunternehmen (sole proprietorship)the most common choice. No minimum capital, simple registration (only Gewerbeanmeldung), accounting via EÜR (simplified income/expense method). Taxes: income tax + trade tax. Full personal liability with private assets.
  • GbR (civil law partnership)for 2+ persons running a craft together. No minimum capital, full personal liability of all partners. Simple form, no notary, also uses EÜR.

There are also corporations (GmbH, UG) with limited liability, but they require double-entry bookkeeping, a notary, and higher operating costs.

BauFin supports all common legal forms in construction — Einzelunternehmer, GbR, GmbH and UG. For Einzelunternehmer and GbR, BauFin provides EÜR (simplified accounting) by default. For GmbH/UG with double-entry bookkeeping, BauFin serves as a central system for orders, payroll and dunning, with DATEV export to the tax advisor.

1.2 Business registration (Gewerbeanmeldung)

Anyone starting a business in Germany must register it at the local trade office (Gewerbeamt) — mandatory under §14 GewO (Trade Regulation Act).

What you need:

  • ID card or passport (EU citizens: no additional permits required)
  • Gewerbeanmeldung form (GewA 1)
  • Entry in the Handwerksrolle (if your craft requires a Meistersee below)
  • Fee: €20-60 depending on municipality

After registration, the Gewerbeamt automatically notifies:

  • Tax office (Finanzamt)you will receive a tax questionnaire
  • Chamber of Commerce (IHK) or Chamber of Crafts (Handwerkskammer)
  • Accident insurance (Berufsgenossenschaft)
  • Statistical office

IMPORTANT: You must register BEFORE starting work. Operating an unregistered business is an administrative offense.

1.3 Chamber of Crafts (Handwerkskammer)

Crafts in Germany are regulated by the Handwerksordnung (HwO). Key distinction:

  • Annex Alicensed crafts requiring Meisterbrief (53 professions). Construction examples: Bricklayers (No. 1), Carpenters (No. 3), Roofers (No. 4), Painters (No. 10), Plumbers (No. 24), Electricians (No. 25), Tilers (No. 42).
  • Annex B1license-free crafts (no Meister required). Examples: Floor layers, Asphalters, Grouters.
  • Annex B2craft-like trades. No Meister required.

If your craft is in Annex A — you need a Meisterbrief OR must employ a Meister as technical manager. Alternative: Ausnahmebewilligung (§8 HwO) — exemption from Meister requirement if you demonstrate equivalent qualifications (e.g. 6+ years of experience).

EU citizens: recognition of foreign qualifications is possible under Directive 2005/36/EC.

1.4 Tax Office — Steuernummer & VAT ID

After Gewerbeanmeldung, the tax office will send you the Fragebogen zur steuerlichen Erfassung (tax registration questionnaire). It must be completed within one month.

Key numbers:

  • Steuernummer (tax number)assigned by your local tax office. Format: XXX/XXX/XXXXX. Required on invoices (§14 UStG), tax returns, and correspondence with the tax office.
  • USt-IdNr (VAT identification number)format: DE123456789. Needed for intra-EU transactions (with companies from other EU countries). Not mandatory for domestic-only business, but recommended.
  • Identifikationsnummer (IdNr)personal 11-digit tax number assigned to every person registered in Germany. Do not confuse with Steuernummer.

The questionnaire asks about:

  • Estimated revenue and profit in the first year
  • Whether you want to use the small business exemption (§19 UStG)
  • Bank details
  • Form of taxation

1.5 Business account & insurance

Business account:

  • Sole proprietorslegally not required to have a separate business account, BUT strongly recommended. Mixing private and business finances is a nightmare during a tax audit.
  • GmbH/UGseparate business account is MANDATORY.
  • Cost: €0-15/month (many banks offer free business accounts).

Mandatory insurance:

  • Health insurance (Krankenversicherung)MANDATORY for everyone in Germany. Self-employed: private (PKV) or voluntary statutory (GKV). Cost: €200-800/month depending on income and plan.
  • Accident insurance (BG Bau)statutory accident insurance, MANDATORY for construction companies. Must register within one week of starting operations.
  • Business liability insurance (Betriebshaftpflicht)not legally required but ESSENTIAL in practice. Without it, you won't get onto most construction sites. Protects against damage claims.

Additional (recommended):

  • Pension insurancemandatory for Annex A craftsmen for the first 18 years (§2 No. 8 SGB VI)
  • Legal protection insurance
  • Disability insurance

How BauFin helps

BauFin stores all company data centrally — tax number, VAT ID, chamber number, bank details. Set up once, used everywhere — on invoices, quotes, and tax returns.

Proper digital bookkeeping under GoBD principles is mandatory. Every invoice, every expense, every receipt must be documented.

2.1 EÜR vs. Balance Sheet — who needs what?

Germany has two accounting methods:

  • EÜR (Einnahmenüberschussrechnung)simplified method: income minus expenses = profit. For: sole proprietors, GbR, freelancers with revenue up to €600,000 OR profit up to €60,000 per year. Most craftsmen use EÜR.
  • Double-entry bookkeeping (Bilanz)full accounting with balance sheet. Mandatory for: GmbH, UG, companies in the commercial register, and businesses exceeding EÜR thresholds.

If you run a sole proprietorship as a craftsman and don't exceed the thresholds — EÜR is sufficient. You record income when received and expenses when paid (cash basis / Zufluss-/Abflussprinzip).

The EÜR is filed annually as an attachment to your income tax return (Anlage EÜR).

2.2 GoBD — Principles of proper bookkeeping

GoBD (Grundsätze zur ordnungsmäßigen Führung und Aufbewahrung von Büchern) are the German rules for digital bookkeeping. They apply to EVERY entrepreneur — including sole proprietors.

Key requirements:

  • Immutability (Unveränderbarkeit)once saved, documents cannot be changed or deleted without a trace. Every change must be logged (who, when, what).
  • Continuous numberinginvoices, documents, bookings must have sequential numbers without gaps. Gaps = red flag for the auditor.
  • 10-year retentioninvoices, bookings, commercial letters: 10 years (§147 AO). Receipts and other correspondence: 6 years.
  • Readabilitydocuments must remain readable throughout the retention period.
  • Procedural documentation (Verfahrensdokumentation)you must describe HOW you manage your bookkeeping.

Violations can result in the tax auditor rejecting your books and estimating your income (Hinzuschätzung) — almost always to your disadvantage.

2.3 Invoices per §14 UStG

Every invoice issued in Germany must contain 8 mandatory elements (Pflichtangaben) per §14 Abs. 4 UStG:

  1. 1.Full name and address of the supplier
  2. 2.Full name and address of the recipient
  3. 3.Tax number OR VAT ID of the supplier
  4. 4.Invoice date
  5. 5.Invoice number — sequential, unique
  6. 6.Quantity and type of service (commercial description)
  7. 7.Date of service (Leistungsdatum)
  8. 8.Net amount + VAT rate + VAT amount (or reference to exemption)

Missing any element = defective invoice. The recipient cannot claim input VAT deduction (§15 UStG).

For small invoices up to €250 gross (Kleinbetragsrechnungen, §33 UStDV), simplified requirements apply.

2.4 Reverse Charge §13b UStG

Reverse Charge shifts the VAT liability to the recipient. In construction, it applies to B2B construction services.

When to apply (§13b Abs. 2 No. 4 in conjunction with Abs. 5 UStG):

  • Service = construction service (Bauleistung)
  • Recipient = construction entrepreneur (≥10% of total revenue from construction services)

Required on §13b invoices:

  • All 8 mandatory elements from §14 UStG
  • Amounts NET (without VAT)
  • Formula: „Steuerschuldnerschaft des Leistungsempfängers” (BMF letter 27.01.2023)
  • Recipient's VAT ID

NOT allowed on §13b invoices:

  • VAT rate, VAT amount, gross amount

WARNING: If you accidentally show VAT on a §13b invoice, you owe it to the tax office (§14c UStG). The recipient must provide USt 1 TG certification before the first §13b invoice.

2.5 E-Invoice (ZUGFeRD & XRechnung)

E-invoices are structured electronic invoices (not PDF scans). Germany uses two standards:

  • ZUGFeRDhybrid: PDF/A-3 with embedded XML file (EN 16931). The recipient sees a normal PDF, the accounting system reads the XML data automatically.
  • XRechnungpure XML, EN 16931 standard. Required for invoices to public institutions (B2G) over €1,000.

Since 01.01.2025, all businesses in Germany must be able to RECEIVE e-invoices. The obligation to ISSUE them is being introduced gradually.

For craftsmen: ZUGFeRD is the simplest solution. The recipient gets a normal-looking PDF whose data can be imported automatically.

2.6 Business expenses & receipts

Every business expense must be documented. Rule: no receipt = no deduction.

Typical business expenses:

  • Building materials, tools
  • Fuel, vehicle costs
  • Phone, internet (business portion)
  • Business insurance
  • Office/workshop rent
  • Work clothing
  • Professional training

§4 Abs. 5 EStG limits certain deductions:

  • Entertainment expenses (Bewirtungskosten)max 70% deductible
  • Business giftsmax €50 per person per year

GoBD requires: receipts must be archived in immutable form for 10 years. Faded thermal receipts — photograph/scan IMMEDIATELY.

2.7 Cash book (Kassenbuch)

If you handle cash transactions (accept cash payments or pay in cash) — you must keep a Kassenbuch (cash book).

Requirements:

  • Record every cash movement: date, amount, description, balance
  • The cash balance must NEVER be negative
  • Entries must be chronological and continuous
  • GoBD: immutabilityrecorded transactions cannot be deleted

The cash book is one of the first documents a tax auditor checks. Negative balance = immediate red flag.

2.8 Trip log, distance allowance & business trips

Travel costs must be separated by trip type:

  • Distance allowance (Entfernungspauschale)from 2026, €0.38 per full kilometer of one-way distance between home and the first workplace (erste Tätigkeitsstätte, §9 Abs. 1 Satz 3 Nr. 4 EStG). The annual cap is generally €4,500, with exceptions including use of an own or provided car.
  • Trip log (Fahrtenbuch)document every trip: date, from, to, purpose, odometer start/end. This prepares the business-use share and vehicle costs for review.
  • External activity/business trip (Auswärtstätigkeit/Dienstreise)if there is no first workplace and the trip is tax-classified as external activity, a private car may use €0.30/km per driven kilometer or actual vehicle costs. German domestic meal allowances depend on absence time (€14/€28).

2.9 Cancelling and correcting invoices — what is NOT allowed

A sent invoice must never be overwritten or deleted — GoBD requires the original record to remain intact and traceable.

Correct ways:

  • Cancellation invoice (Stornorechnung)cancels the whole invoice with negative amounts; then issue a new one.
  • Correction invoice (Rechnungskorrektur)corrects individual items, referring to the number and date of the original.

WARNING: never call your own correction a „Gutschrift". Under German tax law that is a distinct document type (self-billing by the recipient) — using the word risks an unjustified tax statement under §14c UStG.

Why it matters: VAT stated on an invoice is owed to the tax office even if stated incorrectly — until the invoice is properly corrected.

2.10 Payment terms, default and interest

Unless agreed otherwise, default against a business starts automatically the day after the due date — no reminder needed. With 30-day terms, interest runs from day 31.

B2B entitlements on late payment:

  • Statutory interest: base rate plus 9 percentage points. The base rate changes every six monthssince 1 July 2026 it is 1.52 %.
  • A flat 40 € recovery fee, regardless of invoice size and without proof of costs.

Against consumers the rate is lower (base rate plus 5 points) and the 40 € flat fee does not apply.

Early-payment discount (Skonto) is voluntary — if you offer it, state the terms on the invoice, e.g. „2 % if paid within 10 days".

How BauFin helps

BauFin creates invoices with §14 UStG fields, supports Reverse Charge §13b hints, archives receipts with SHA-256 checksums and manages the cash book and trip log. GoBD-oriented use also depends on setup, working process and procedural documentation.

Working time regulations in construction are strict. BRTV, holidays, SOKA-BAU — find out everything here.

3.1 BRTV — Collective working hours (38h/41h)

Working hours in construction are regulated by the BRTV (Federal Framework Collective Agreement for Construction), §3 No. 1.1. The standards are SEASONAL:

  • Winter (January-March, December)38h/week. Monday-Thursday 8h each, Friday 6h.
  • Summer (April-November)41h/week. Monday-Thursday 8.5h each, Friday 7h.

Annual average: 40h/week.

IMPORTANT: FRIDAY IS ALWAYS SHORTER — this is a fundamental feature of the German construction industry. Saturday and Sunday = off (unless overtime is agreed).

Employees with individual contracts may have different standards, but BRTV is the industry minimum.

3.2 Federal holidays in Germany

Germany has 9 holidays observed in all federal states (Bundesländer):

Fixed dates:

  • January 1New Year's Day (Neujahr)
  • May 1Labor Day (Tag der Arbeit)
  • October 3German Unity Day
  • December 25Christmas Day
  • December 262nd Christmas Day

Movable (dependent on Easter):

  • Good Friday (Karfreitag)2 days before Easter
  • Easter Monday (Ostermontag)1 day after Easter
  • Ascension Day (Christi Himmelfahrt)39 days after Easter
  • Whit Monday (Pfingstmontag)50 days after Easter

WARNING: Individual states may have additional holidays (e.g. Reformation Day, Corpus Christi). Check your state's regulations.

Holidays falling on Saturday/Sunday do NOT reduce the week's target hours.

3.3 Minimum wage & construction industry wage

Germany has two minimum wage levels:

  • Statutory minimum wage (Mindestlohn)€13.90/hour gross (as of 2026). Applies to ALL employees in Germany, no exceptions.
  • Construction industry minimum wage (Branchenmindestlohn Bau)HIGHER than the statutory minimum. Set by collective agreement, declared generally binding by BMAS. Applies to ALL construction companies in Germany — including non-union ones.

The construction wage is tiered by pay groups (Lohngruppen). Current rates are available from SOKA-BAU or BMAS — they change every 1-2 years.

IMPORTANT: Paying below minimum wage is a criminal offense. Zoll (German customs) regularly inspects construction sites.

3.4 SOKA-BAU obligation

SOKA-BAU (Construction Industry Social Fund) is the industry social fund for construction. Membership is MANDATORY for most construction companies in Germany.

What SOKA-BAU covers:

  • Vacation fund (Urlaubskasse)construction workers get 30 vacation days. Employer pays contributions, SOKA-BAU pays out vacation pay.
  • Supplementary pension (Zusatzversorgung)additional retirement provision for construction workers.
  • Vocational training (Berufsbildung)professional education and training.

Employer contributions: approx. 15-20% of gross wages (exact rate depends on year and group). Monthly payment to SOKA-BAU.

IMPORTANT: As a sole proprietor WITHOUT employees, you don't need to pay SOKA-BAU contributions. The obligation only arises when you hire an employee.

3.5 Payroll — basics

If you employ staff, you must run payroll (Lohnabrechnung). Every employee must receive a monthly pay slip (Lohnzettel).

Mandatory deductions from gross pay:

  • Income tax (Lohnsteuer)advance payment on income tax (amount depends on employee's tax class)
  • Solidarity surcharge5.5% of income tax (only at higher incomes)
  • Church tax8-9% of income tax (if employee is a church member)
  • Health insurance~7.3% + supplementary contribution (split equally employer/employee)
  • Pension insurance9.3% (split equally)
  • Unemployment insurance1.3% (split equally)
  • Care insurance~1.7% (split equally, higher for childless)

As employer, you remit deductions monthly to the tax office (taxes) and health insurer (social security). Obligation: immediate notification (Sofortmeldung) to SOKA-BAU on the day of hiring a new construction worker (§28a SGB IV).

How BauFin helps

BauFin knows BRTV standards: 38h in winter, 41h in summer, shorter Fridays. Working hours are automatically compared with target hours. Holidays calculated dynamically for each year. Time tracking per employee.

Anyone working with subcontractors needs to know about construction withholding tax and exemption certificates.

4.1 Exemption certificate §48b EStG

The Freistellungsbescheinigung (exemption certificate) is a tax office document that exempts the client from withholding 15% construction tax.

When you need it:

  • You commission a subcontractor for construction work
  • Subcontractor has NO exemption certificateyou MUST withhold 15% from their invoice and pay it to the tax office
  • Subcontractor HAS a valid certificateyou pay the full amount

How it works:

  • The subcontractor applies at their tax office
  • The tax office issues the certificate with a validity date (usually 1-3 years)
  • You can verify authenticity through BZSt (Federal Central Tax Office)

WARNING: Always check the expiry date! Expired certificate = must withhold 15%.

4.2 Construction withholding tax — 15% deduction

Bauabzugsteuer (§48 EStG) is a mandatory 15% withholding from payment for construction services.

Who withholds: the client (Auftraggeber) — that's YOU when you hire subcontractors.

When to withhold:

  • The subcontractor has no exemption certificate
  • OR the certificate has expired

What to do with the withheld 15%:

  • File a Bauabzugsteuer declaration with the tax office (by the 10th of the following month)
  • Transfer the withheld amount to the tax office

If you DON'T withhold when you should — YOU are liable for the 15% (§48a EStG). The tax office will collect it from you, not from the subcontractor.

Calculation basis: the 15 % is calculated on the GROSS amount (fee plus VAT), not on the net. On a 10,000 € net invoice (11,900 € gross) that is 1,785 €, not 1,500 €.

4.3 Reverse Charge on subcontractor invoices

If you receive an invoice from a subcontractor for construction services as a construction entrepreneur — it will most likely be a §13b invoice (Reverse Charge). This means:

  • The invoice is NET (without VAT)
  • It states „Steuerschuldnerschaft des Leistungsempfängers”
  • YOU as recipient must declare the VAT in your UStVA
  • At the same time you can deduct the same VAT (input tax deduction)net effect = zero

In practice with B2B construction Reverse Charge: you pay the subcontractor net, the VAT is settled “on paper” in your declaration.

IMPORTANT: Check whether the subcontractor has the USt 1 TG certificate (proof of construction entrepreneur status).

4.4 Contractual protection

Working with subcontractors requires legal protection. Minimum:

  • Written contract (Werkvertrag or subcontractor agreement)scope of work, deadline, payment, terms
  • Copy of subcontractor's business registration (Gewerbeanmeldung)
  • Copy of exemption certificate §48b EStG (current!)
  • Copy of liability insurance (Betriebshaftpflicht)
  • A1 certificate (if subcontractor from another EU country)
  • USt 1 TG (for §13b invoices)

Without these documents you risk:

  • Liability for subcontractor's social security contributions (Nachunternehmerhaftung)
  • Fines for illegal employment (Schwarzarbeit)
  • Liability for construction withholding tax

Archive all subcontractor documents — the auditor will check them during a Betriebsprüfung.

4.5 Scheinselbstständigkeit — bogus self-employment

This is the biggest financial risk when working with subcontractors. It applies when someone is formally self-employed but in practice works like an employee. What counts is the actual arrangement, not the contract title.

Criteria:

  • Being bound by instructions on time, place and manner of work
  • Integration into the client organisation, working with their equipment
  • No entrepreneurial risk of your own

Employing your own staff or subcontractors speaks for genuine self-employment.

Consequences for the CLIENT: retroactively treated as an employer, owing the FULL social security contributions (both employer and employee share) — normally up to 4 years back, and up to 30 years in cases of intent, plus interest, surcharges and possible criminal liability.

How BauFin helps

BauFin manages exemption certificates with expiry warnings and can prepare construction withholding tax calculations and documents for review and filing. Complete subcontractor file with all documents.

Income tax, VAT, trade tax — as a business owner you have several tax obligations.

5.1 Income tax — rates & advance payments

Einkommensteuer (income tax) is the main tax for sole proprietors. You pay it on profit (income minus expenses from EÜR).

Tax brackets 2026 (§32a EStG):

  • Up to €11,7840% (basic allowance, Grundfreibetrag)
  • €11,785 - €17,00514-24% (progressive)
  • €17,006 - €66,76024-42%
  • €66,761 - €277,82542%
  • Above €277,82645% (Reichensteuer)

Quarterly advance payments (Vorauszahlungen): set by the tax office based on your last return. Due: March 10, June 10, September 10, December 10. Late payment = 0.5%/month surcharge.

Annual return (Einkommensteuererklärung): deadline — July 31 of the following year (with tax advisor: end of February two years later).

5.2 VAT — declarations & advance returns

Umsatzsteuer (VAT) — 19% standard rate, 7% reduced (for food, books etc. — rarely relevant in construction).

Declarations:

  • UStVA (advance VAT return)monthly or quarterly preliminary declaration. Deadline: 10th of the following month. Can be extended by one month (Dauerfristverlängerung).
  • Annual VAT returnannual declaration. Same deadline as income tax.

Monthly or quarterly:

  • First year of businessALWAYS monthly
  • VAT liability > €7,500/yearmonthly
  • VAT liability €1,000-7,500quarterly
  • VAT liability < €1,000exemption from UStVA possible (annual return only)

IMPORTANT: UStVA is filed electronically via ELSTER. Non-filing = late filing penalty (Verspätungszuschlag).

5.3 Small business regulation §19 UStG

The Kleinunternehmerregelung exempts small businesses from VAT.

Requirements (§19 UStG):

  • Revenue in PREVIOUS year ≤ €25,000
  • Revenue in CURRENT year ≤ €100,000 (estimated)

If both conditions are met — you can opt out of charging VAT. Consequences:

  • No VAT on your invoices
  • No UStVA (advance returns)
  • BUT: no input VAT deduction from purchase invoices (no Vorsteuerabzug)

For craftsmen who buy lots of materials, the Kleinunternehmerregelung often does NOT pay off — losing the input VAT deduction outweighs the simplicity. Calculate before you decide.

Opting out of the regulation binds you for 5 years (§19 Abs. 2 UStG).

5.4 Trade tax — exemption & calculation

Gewerbesteuer (trade tax) is a local tax paid to the municipality.

Who pays: every business owner (Gewerbetreibender). Freelancers (Freiberufler) do NOT pay.

Calculation:

  • Base: business profit
  • Exemption (Freibetrag): €24,500for sole proprietors and GbR. Earn less = no trade tax.
  • Tax base rate (Steuermessbetrag): 3.5% of the amount exceeding the exemption
  • Municipal multiplier (Hebesatz): varies by municipality (e.g. Hamburg: 470%, Berlin: 410%)

Example: €50,000 profit in Hamburg: (50,000 - 24,500) × 3.5% × 470% = ~€4,193 trade tax.

BUT: Sole proprietors can credit trade tax against income tax (§35b EStG, max. 4× tax base rate). In many cases trade tax is effectively neutral.

5.5 Church tax & solidarity surcharge

Church tax (Kirchensteuer):

  • Paid by members of the Catholic or Protestant church in Germany
  • Rate: 8% (Bavaria, Baden-Württemberg) or 9% (other states) of income tax
  • You can leave the church (Kirchenaustritt)then you don't pay
  • For many foreign craftsmen: if you haven't joined a church in Germanyyou don't pay

Solidarity surcharge (Solidaritätszuschlag):

  • 5.5% of income tax
  • Since 2021: only at higher incomes. Most sole proprietors with typical craftsman income do NOT pay Soli.
  • Threshold: income tax > €18,130 (single) / €36,260 (married)below that: 0%.

5.6 Permanent filing extension — watch the special prepayment

Extending the VAT filing deadline by one month comes with a catch:

  • With MONTHLY filing a special prepayment (Sondervorauszahlung) of 1/11 of last year VAT is due, offset later in the annual return.
  • With QUARTERLY filing there is no special prepayment.
  • The application is filed electronically via ELSTER.

In practice: you ask for more time and receive a one-off charge — plan for it.

How BauFin helps

BauFin creates the EÜR, calculates VAT return values, tracks tax advance payments with deadline warnings, and exports data in DATEV format for your tax advisor.

Legal tax optimization can save craftsmen thousands of euros per year.

6.1 Travel costs without primary workplace (§9 para. 4a)

If the tax classification shows no first workplace and the trip is external activity/business travel, document the route as a business trip: for a private car, generally €0.30/km per driven kilometer or actual vehicle costs, plus German domestic meal allowances by absence time (€14/€28) and documented accommodation costs. The actual effect depends on the case and tax-advisor review.

6.2 GWG, IAB, AfA

  • GWG (§6 Abs. 2 EStG)instant write-off of movable assets up to €800 net
  • IAB (§7g EStG)deduct 50% of planned investment before purchase (profit ≤ €200,000)
  • AfA (§7 EStG)straight-line or declining balance depreciation per official BMF tables

6.3 Home office & phone

  • Homeoffice allowance: €6/day, max €1,260/year
  • Phone/Internet: 20% of the bill, max €20/month (simplified method)

How BauFin helps

The tax optimization module in BauFin analyzes your data and identifies savings potential — from travel costs to depreciation.

A tax audit can happen to anyone. Those who are prepared have nothing to fear.

7.1 How to prepare

A Betriebsprüfung (tax audit) can affect any entrepreneur. The tax office selects businesses based on various criteria — randomly, after unusual returns, or following a tip-off.

How to prepare:

  • Keep bookkeeping currentdon't leave it to the last minute
  • Archive ALL documentsinvoices, receipts, contracts, correspondence
  • Maintain continuous invoice numbering
  • Cash book always up to date, balance never negative
  • Procedural documentation ready (see below)
  • Subcontractor documents complete (exemption certificate, A1, contracts)

The auditor typically gives 2-4 weeks notice. You have the right to have a tax advisor present during the audit.

7.2 What the auditor checks

The tax auditor primarily checks:

  • Income completenessare all invoices recorded, do bank transactions match invoices
  • Expensesdocumented, business-related, not private
  • Cash bookcompleteness, balance, consistency with deposits/withdrawals
  • Invoice numberingsequential, no gaps
  • VATcorrectly calculated and remitted, Reverse Charge correctly applied
  • Subcontractorsexemption certificates, construction withholding tax, A1
  • Trip logif vehicle costs are claimed
  • GoBDdata immutability, change log, archiving

The auditor has the right to access your bookkeeping system (Z1/Z2/Z3 data access). That's why you must be able to export data in GDPdU format.

7.3 Procedural documentation — GoBD requirement

The Verfahrensdokumentation describes HOW you organize your bookkeeping. Mandatory since GoBD introduction.

Content:

  • Description of the bookkeeping system (which software, which modules)
  • Procedures: how invoices are created, receipts archived, VAT calculated
  • Access rights: who can access data, who can make changes
  • Backup: how and where data is backed up
  • IT security: description of protective measures

Missing procedural documentation is a formal deficiency — the auditor can challenge your entire bookkeeping.

In practice, most small businesses don't have one. That doesn't mean you can skip it — it means most businesses aren't prepared for an audit.

7.4 GDPdU export — data for the auditor

GDPdU (Principles for Data Access and Auditability of Digital Documents) govern providing digital data to the auditor.

Three access levels (Z1/Z2/Z3):

  • Z1 (direct access)the auditor views data in your system
  • Z2 (indirect access)the auditor requests you generate reports
  • Z3 (data carrier transfer)the auditor requests data on a medium in a specified format

Export format: CSV or XML with structure description. The auditor uses the IDEA tool (Interactive Data Extraction and Analysis) for analysis.

What must be exported:

  • All invoices (issued and received)
  • Bookings (EÜR)
  • Cash book
  • Customer and subcontractor data
  • Change log (Audit Trail)

If data cannot be delivered, the auditor can impose a delay penalty (Verzögerungsgeld) of up to €25,000 per request.

How BauFin helps

BauFin supports procedural documentation, GDPdU export and GoBD-oriented document archiving with SHA-256 checksums. Audit-relevant documents remain traceable; professional review remains part of the process.

Craftsmen from Poland, Romania, Croatia, Türkiye and Ukraine face different rules — five countries of origin, five legal situations covering residence, double taxation, social security and child benefit. We have set them out separately instead of squeezing them into this guide.

Overview by country of origin