Invoicing is the part of translation work that nobody trained you for. Language schools teach glossary management and CAT tool shortcuts — they don't teach you how to bill a client in Japan from Tashkent, what "net 30" means when a client ignores it, or why PDF attachments to Gmail occasionally sink a payment. This guide covers all of it.

Why Translation Invoicing Is Different

Freelance translation has a billing quirk that almost no other creative field shares: your price depends on a unit (words, hours, pages) that changes with every project. A copywriter sends a flat quote. A developer invoices by the hour. You invoice by source words, target words, weighted words, or some combination — and your client may have their own definition of each.

This means translation invoicing software needs to do something general invoicing tools do not: pull word counts directly from your CAT environment, apply segment-level weighting (100% match, fuzzy, no-match), and produce a line-item breakdown that clients can verify against their own counts.

Using a general-purpose tool like FreshBooks or Wave forces you to manually enter word count data from your translation memory report into a separate system. That introduces transcription errors and doubles your administrative time.

Setting Your Rates

Before you can invoice, you need defensible rates. The most common billing models for freelance translators:

Per source word — you charge based on the original text word count. Predictable for the client, easy to quote before the job starts. Most common in the Western European market.

Per target word — you charge based on the translated output. Favored in some language pairs where the target language is reliably longer (e.g., English to German). Riskier without a cap if the client's source text is unusually dense.

Per hour — common for editing, proofreading, transcreation, and post-editing machine translation (PEMT). Requires time-tracking discipline. Clients sometimes push back without a detailed timesheet.

Weighted words — you apply different rates to different match categories from your translation memory. A 100% TM match might bill at 25% of your full rate; a fuzzy match at 65%; a new segment at 100%. This model rewards clients for TM leverage while protecting your time on novel content.

For most freelancers starting out, the recommendation is to bill by source word at a single rate and graduate to weighted word billing once you have a populated translation memory and enough leverage to negotiate. KanCAT's pricing page includes a free tier that supports basic weighted word billing on small volumes.

What to Include on Every Translation Invoice

A compliant translation invoice needs these fields regardless of jurisdiction:

  • Your name and address (or business name if you operate as a company)
  • Client name and billing address
  • Invoice number — sequential, never reuse
  • Invoice date and payment due date
  • Line items: source language, target language, word count, unit rate, amount
  • TM discount breakdown (if applicable) — show gross before discount, then discount as a negative line
  • Subtotal, any applicable tax (VAT/GST), total
  • Payment instructions: bank details or payment link

If you work across EU clients, include your VAT number if registered. For B2B cross-border invoices within the EU, the reverse charge mechanism applies — include the note: "VAT: Reverse charge — Article 196 of Council Directive 2006/112/EC."

For non-EU clients, check whether the destination country requires any specific invoice formatting. Most don't — a clean English-language invoice with the fields above will clear most AP departments.

Common Invoicing Mistakes That Delay Payment

Not specifying payment terms upfront. "Net 30 from invoice date" and "net 30 from receipt of invoice" are different. State it in your contract and repeat it on the invoice.

Vague line item descriptions. "Translation services — April" tells the AP clerk nothing. "EN→DE translation, 4,280 source words @ $0.12/word, Project ID: KC-2026-041" is auditable.

Using a personal PayPal for business payments. Many enterprise clients won't pay to personal PayPal. Set up a business account, or use a wire transfer with a proper SWIFT/IBAN reference.

No late payment policy. Add a clause to your contract: "Invoices unpaid after 30 days accrue interest at 2% per month." Most clients will never trigger it — but it changes the psychological calculus.

Sending invoices as editable Word documents. Always send PDF. Editable formats have been modified by unscrupulous clients to change amounts. PDF with the original filename and a SHA-256 hash in the file metadata is even better.

Using Translation Invoicing Software in Your Workflow

The most efficient freelance translation workflow connects your CAT tool to your billing tool directly:

  1. Complete translation segments in your CAT environment
  2. The CAT tool reports word counts by match category
  3. Invoicing software pulls the word count, applies your rates and TM discounts
  4. You review the draft invoice, adjust if needed, and export to PDF
  5. The invoice is sent to the client from the same tool that tracked the project

KanCAT's features page describes how this works in practice: the platform tracks segment-level word counts during translation, lets you define per-client rate cards with TM discount percentages, and generates PDF invoices in one step from the completed project. No data entry, no copy-paste errors.

For solo translators, the free plan supports up to 3 invoices per month — enough to cover a typical month of client work before you need to upgrade.

Late Invoices and Collection

If a client is late, your sequence should be:

  1. Day 31: Polite reminder. Attach the original invoice PDF again — AP departments lose attachments.
  2. Day 45: Second reminder, reference your late payment clause.
  3. Day 60: Formal notice. State the accrued interest amount. If you are in the UK, you can claim statutory interest under the Late Payment of Commercial Debts Act.
  4. Day 75+: Escalation — small claims court (UK), debt collection agency, or professional association complaint channel.

Prevention is better than collection. Screen new clients by asking for a purchase order number before starting work. A client who can issue a PO has a real finance department. A client who can't might be running on an overdraft.

Building a Translation Invoicing System That Scales

As your volume grows, manual invoicing becomes unsustainable. A structured system has three layers:

Rate cards: maintain a per-client rate table (language pair, rate, discount schedule). Review annually.

Project tracking: every project has a reference number, source/target word count, and due date tracked before you start translating.

Invoice templates: consistent formatting, pre-filled from project data, no manual entry.

This is exactly what translation invoicing software is built to automate. Whether you use KanCAT or a combination of tools, the goal is the same: zero manual data transfer between your CAT environment and your billing output.

The administrative side of freelance translation is learnable in an afternoon. The hard part is building the habit — invoicing on the day of delivery, not two weeks later. Start with a clean template, use KanCAT's free tier to connect your project data to your invoices, and treat billing as part of the translation process rather than a chore you defer.