What an Invoice Must Contain: A Guide for International Clients

A new client in Berlin or Tel Aviv asks for an invoice before releasing the first payment, and the Russian schet — you normally send suddenly looks insufficient. A foreign accounts-payable clerk expects English wording, a due date, a currency and a tax line they can book without writing back to you. Below is what an invoice for an international client must contain, what to write in the VAT field when you are not tax-registered, how Russian identifiers fit into the document, and an eight-point checklist to run before you press send.

Invoice vs schet: same idea, different expectations

The Russian schet na oplaty and the English invoice do the same job: both ask a buyer to pay a stated amount for an itemized list of goods or services, and neither has a single legally mandated form. The difference is in bookkeeping habits. A Russian schet is built around INN, KPP and rubles; an invoice is built around a unique number, an issue date, a due date, a currency and a tax identification that the buyer's finance team can verify.

For a foreign client you issue a document titled Invoice, written in English, denominated in the agreed currency. It does not replace the paperwork you keep at home: your own accounting records and tax reporting continue under the rules of your regime. The invoice is what the client's AP department will match against their purchase order and bank transfer, so it must answer four questions at a glance: who is billing whom, for what, for how much, and by when.

Mandatory fields of an international invoice

Layouts differ between tools and countries, but the field set that buyers and auditors expect is fairly stable:

• invoice number: unique and sequential, ideally with a year prefix such as 2026-047;
• issue date and due date: when the invoice was sent and when payment must arrive;
• seller block: legal or trading name, full address, and your tax identifier;
• buyer block: the client's registered name and address, as it appears in their registration documents rather than in an email signature;
• one line per service or product, with a description, quantity, unit and unit price;
• line totals, then a subtotal, a tax line and a grand total, each on its own row;
• currency stated explicitly next to every amount, EUR 330.00 rather than a bare 330.00;
• payment terms: the deadline (Net 14, Net 30, a fixed date) and the method;
• bank details or a payment link that matches the seller name on the invoice;
• a billing contact for questions: an email that a human actually reads.

A missing due date is the single most common reason international payments arrive late: without a deadline the bill simply waits for the client's next payment run, which can be weeks away. Every other field on the list has the same character. Each one exists because some clerk, auditor or compliance officer once had to reconstruct a deal from paper alone.

What to write in the VAT field when you are not registered

The tax line causes the most confusion on a first international invoice. If you are not registered for VAT, GST or sales tax anywhere, do not display a zero percentage as though tax had been calculated; write VAT: Not applicable, or Not VAT registered. A bare 0% invites the booking system to treat the supply as a zero-rated one, and correcting a posted invoice later is far harder than writing the right words the first time.

Some buyers ask for the phrase VAT reverse charge on business-to-business invoices inside the EU, where the customer accounts for the tax under the reverse-charge mechanism. That wording is only correct in specific situations and depends on registration thresholds and country rules that change periodically, so check the current requirements before adding it. When in doubt, a plain Not applicable line plus a sentence in the covering email is safer than a confident formula you cannot defend.

INN and KPP: keep the identifiers, skip the translation

Russian tax identifiers do not translate into English. INN, the taxpayer identification number, goes into the invoice as INN followed by the digits, the same way an EU VAT number or a US EIN would appear. KPP, the registration-reason code carried by Russian legal entities, has no foreign equivalent and no meaning outside Russian bookkeeping: transliterate it as KPP where a client insists, or omit it entirely. A sole proprietor in Russia has no KPP at all, and an invoice with an empty KPP field is not an error.

What a foreign buyer actually checks is consistency. The name on the invoice must match the name on the contract, on the bank account receiving the money and on any tax identifier quoted. If you trade as an individual, invoice under your own name with your INN. When a client demands a corporate entity you do not legally have, that is a signal to agree on the structure before invoicing, not to improvise a company name on the document.

A sample invoice, line by line

You can draft the document in a free invoice generator and adjust the wording to your case. A minimal international invoice for freelance work looks like this:

Invoice #2026-047                  Date: 12 Nov 2026
Due date: 26 Nov 2026              Terms: Net 14

From: Anna Smirnova, sole proprietor, INN 771234567890
      125167 Moscow, Russia, billing@smirnova.example
To:   Muster GmbH, Hanauer Landstr. 100,
      60314 Frankfurt am Main, Germany

1. WordPress site setup        1 x EUR 250.00 = EUR 250.00
2. SEO consultation, 2 hours   2 x EUR 40.00  = EUR 80.00

Subtotal:   EUR 330.00
VAT:        Not applicable (not VAT registered)
Total due:  EUR 330.00 (three hundred thirty euros, 00 cents)

Payment terms: Net 14, SWIFT bank transfer, details attached.
Payee: Anna Smirnova (as above).

Three details in this sample prevent the classic disputes. The due date turns payment into a deadline instead of a favor. The VAT line tells the buyer's tax team exactly how to book the amount, before anyone writes back with a question. The amount in words works as a checksum: a mistyped digit in the figures cannot quietly survive it. Notice how the Russian INN sits in the seller block like any other tax identifier, unexplained and untranslated, exactly where the client expects to find one.

Payment terms and late payments

Net 14 means payment within fourteen calendar days of the invoice date; Net 30 gives the client a month. State the terms in the invoice header and repeat them in the covering email, because the email is often what the client actually reads. If you charge late interest, say it once and plainly, for example: late payments accrue interest as agreed in the contract. Statutory default interest exists in most jurisdictions, but the rate and conditions differ by country, so phrase your own clause carefully and check the rules that govern your specific contract.

Currency and transfer costs deserve a line of their own. Banks and payment processors subtract fees along the way, so a EUR 330 invoice can land as EUR 322. Either price the fees into your rate or state that the payer covers transfer charges. On a one-off invoice the gap looks like a rounding error; on a monthly retainer it becomes a monthly reconciliation exercise with the finance team.

Common mistakes on first international invoices

1. No due date. Without a deadline the invoice joins an open queue and gets paid in the next bulk run, sixty days later, with nobody technically at fault.
2. Missing or ambiguous currency. The figures arrive, the payer converts them at their own rate, and the received amount no longer matches what you expected.
3. Translating tax identifiers. Describing the INN in a long English phrase where a short code belongs creates confusion; the identifier should stay a code.
4. Invoicing a company name you do not legally represent. The payer checks the payee name against the account holder, and a mismatch freezes the payment.
5. A VAT rate shown without being registered for it. Once the buyer books your invoice with tax on it, correcting the record takes a credit note and a new invoice.
6. Amount in digits only. A mistyped 330 becomes 3,300 and nobody notices until the transfer arrives ten times larger than expected. Check the words with an amount in words tool whenever you bill in a language you rarely write.

Checklist before you press send

1. The client's registered name and address come from their registration extract, not from an email signature.
2. Your own name, address and tax identifier match the bank account that will receive the money.
3. The invoice number follows your sequence; the issue date is the real sending date.
4. Every line has a quantity and a unit price, and the lines add up to the total.
5. The tax line states your actual registration status in plain words.
6. The total is duplicated in words, and both forms agree.
7. Payment terms name a due date, a currency and a method.
8. You have saved the PDF and the editable source, and the email with the attachment stays in your sent folder.

One habit ties the whole document together: dates. Invoice date, due date and payment date must line up across your records, the records and the bank statement. The date formatter converts between ISO dates and the day-month-year style most European finance teams write, which is handy when the same engagement produces a contract in one format and an invoice in another.