The BU key (Buchungsschlüssel or Steuerschlüssel) tells DATEV how to treat VAT on a booking. 3 means 19% output VAT, for example, and 9 means 19% input VAT. Newer three-digit keys replace many two-digit ones, such as 240 instead of 10 for OSS distance sales. DATEV's 2026 table lists both.

Why do some accounts need no tax key?

Many revenue accounts are automatic accounts (marked AM in the DATEV chart). The tax treatment is built in, such as 19% on 8400 in SKR03. An extra key on those accounts isn't expected and quickly leads to the error “Ungültiger BU-Schlüssel”.

Which DATEV account do I use for OSS sales?

For distance sales of goods to consumers in other EU countries, DATEV provides accounts 8320-8329 (SKR03) or 4320-4329 (SKR04), and 8331 or 4331 for electronic services. Neither is an automatic account: the booking needs key 240 or 280, the EU country and that country's VAT rate.

Once your distance sales and electronic services to consumers in other EU countries together exceed €10,000 net in a calendar year, or did in the previous year. Below that, German VAT applies unless you opt into OSS voluntarily.

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No. The rules load with the page and run in your browser. We only count that the tool was used, not what you selected.

DATEV BU key finder for OSS, EU and export sales

Result

Taxable in Germany, 19%

Revenue account: SKR03 8400 / SKR04 4400
Tax key: 3, built into the account
UStVA field: 81
Legal basis: § 1 Abs. 1 Nr. 1, § 12 Abs. 1 UStG

Automatic account: the tax follows from the account, so the booking's BU field stays empty.

Result

Taxable in Germany, 7%

Revenue account: SKR03 8300 / SKR04 4300
Tax key: 2, built into the account
UStVA field: 86
Legal basis: § 1 Abs. 1 Nr. 1, § 12 Abs. 2 UStG

Automatic account: the tax follows from the account, so the booking's BU field stays empty.

Result

VAT-exempt intra-EU supply

Revenue account: SKR03 8125 / SKR04 4125
Tax key: 231 (two-digit: 11), built into the account
UStVA field: 41
Legal basis: § 4 Nr. 1 b, § 6a UStG
Also in the booking: Customer's VAT ID

Automatic account: the tax follows from the account, so the booking's BU field stays empty.
Also reported in the EC Sales List (ZM)
Exempt only with the customer's valid VAT ID from another EU country and proof that the goods left Germany. The VAT ID goes into the booking's EU information.

Result

Service to an EU business (reverse charge)

Revenue account: SKR03 8336 / SKR04 4336
Tax key: 270 (two-digit: 47), built into the account
UStVA field: 21
Legal basis: § 3a Abs. 2, § 18b Satz 1 Nr. 2 UStG
Also in the booking: Customer's VAT ID

Automatic account: the tax follows from the account, so the booking's BU field stays empty.
Also reported in the EC Sales List (ZM)
The invoice shows no German VAT and states that the customer is liable for the tax (reverse charge).

Result

Distance sale to EU consumers (OSS)

Revenue account: SKR03 8320 / SKR04 4320
Tax key: 240 (two-digit: 10)
UStVA field: 45
Legal basis: § 3c, § 18j UStG
Also in the booking: EU country (destination), Destination country's VAT rate

Not an automatic account: the booking has to carry the tax key.
Reported through OSS to the BZSt, not with German VAT
The destination country's VAT rate applies. Account 8320 / 4320 is not an automatic account, so the booking must carry the key plus the EU country and its rate. DATEV reserves 8320-8329 / 4320-4329 for splitting by country.

Result

Distance sale below the threshold, German VAT 19%

Revenue account: SKR03 8315 / SKR04 4315
Tax key: 221 (two-digit: 13), built into the account
UStVA field: 81
Legal basis: § 3c Abs. 4 UStG

Automatic account: the tax follows from the account, so the booking's BU field stays empty.
Only while distance sales and electronic services to EU consumers together stay under €10,000 net in the current and previous year, and you haven't opted into OSS voluntarily.

Result

Distance sale below the threshold, German VAT 7%

Revenue account: SKR03 8310 / SKR04 4310
Tax key: 222 (two-digit: 12), built into the account
UStVA field: 86
Legal basis: § 3c Abs. 4 UStG

Automatic account: the tax follows from the account, so the booking's BU field stays empty.
Only while distance sales and electronic services to EU consumers together stay under €10,000 net in the current and previous year, and you haven't opted into OSS voluntarily.

Result

Electronic service to EU consumers (OSS)

Revenue account: SKR03 8331 / SKR04 4331
Tax key: 280 (two-digit: 44)
UStVA field: 45
Legal basis: § 3a Abs. 5, § 18j UStG
Also in the booking: EU country (destination), Destination country's VAT rate

Not an automatic account: the booking has to carry the tax key.
Reported through OSS to the BZSt, not with German VAT
The VAT rate of the customer's country applies. Account 8331 / 4331 is not an automatic account: the key, EU country and rate go into the booking.

Result

Electronic service below the threshold, German VAT 19%

Revenue account: SKR03 8449 / SKR04 4449
Tax key: 226, built into the account
UStVA field: 81
Legal basis: § 3a Abs. 5 Satz 3 UStG

Automatic account: the tax follows from the account, so the booking's BU field stays empty.
Only below the shared €10,000 net threshold for distance sales and electronic services to EU consumers, and without opting into OSS.

Result

Electronic service below the threshold, German VAT 7%

Revenue account: SKR03 no standard account / SKR04 no standard account
Tax key: 227
UStVA field: 86
Legal basis: § 3a Abs. 5 Satz 3 UStG

DATEV has no standard account for this case (e.g. e-books). Your Steuerberater creates a revenue account or books with key 227 on an account without automatic tax.

Result

VAT-exempt export (outside the EU)

Revenue account: SKR03 8120 / SKR04 4120
Tax key: 173, built into the account
UStVA field: 43
Legal basis: § 4 Nr. 1 a, § 6 UStG

Automatic account: the tax follows from the account, so the booking's BU field stays empty.
Exempt only with proof of export, usually the customs exit confirmation. Import VAT and duties in the destination country are a separate matter.

Result

Service outside the EU, not taxable in Germany

Revenue account: SKR03 8338 / SKR04 4338
Tax key: 191, built into the account
UStVA field: 45
Legal basis: § 3a Abs. 2 bzw. Abs. 4 Satz 2 Nr. 13 UStG

Automatic account: the tax follows from the account, so the booking's BU field stays empty.
VAT may still be due in the customer's country, for example on digital services to consumers in Switzerland, Norway or the UK.

General rule: services to consumers are taxed where you are, so with German VAT. There are exceptions, for example for services related to property, events or passenger transport. This tool doesn't model them.

General rule: German VAT. For certain services to consumers outside the EU, such as consulting, advertising or legal services (§ 3a Abs. 4 UStG), the sale isn't taxable in Germany. Check with your Steuerberater.

Case	SKR03 / SKR04	Key
Customer in Germany, 19%	8400 / 4400	3
Customer in Germany, 7%	8300 / 4300	2
EU business with VAT ID, goods	8125 / 4125	231 (11)
EU business with VAT ID, services	8336 / 4336	270 (47)
EU consumer, goods, OSS	8320 / 4320	240 (10)
EU consumer, goods, below threshold, 19%	8315 / 4315	221 (13)
EU consumer, goods, below threshold, 7%	8310 / 4310	222 (12)
EU consumer, electronic service, OSS	8331 / 4331	280 (44)
EU consumer, electronic service, below threshold, 19%	8449 / 4449	226
EU consumer, electronic service, below threshold, 7%	-	227
EU consumer, other service (general rule)	8400 / 4400	3
Outside the EU, goods (export)	8120 / 4120	173
Outside the EU, business, service	8338 / 4338	191
Outside the EU, consumer, electronic service	8338 / 4338	191
Outside the EU, consumer, other service (general rule)	8400 / 4400	3

DATEV tax key and revenue account finder

Taxable in Germany, 19%

Taxable in Germany, 7%

VAT-exempt intra-EU supply

Service to an EU business (reverse charge)

Distance sale to EU consumers (OSS)

Distance sale below the threshold, German VAT 19%

Distance sale below the threshold, German VAT 7%

Electronic service to EU consumers (OSS)

Electronic service below the threshold, German VAT 19%

Electronic service below the threshold, German VAT 7%

VAT-exempt export (outside the EU)

Service outside the EU, not taxable in Germany

All cases at a glance

What this tool doesn't cover

Frequently asked questions