One API, countless use cases.

Discover how LetterAPI simplifies sending business communication like invoices, contracts, direct mailings, account statements and many more via postal mail.

Get started, it's free Open API documentation

Invoice mailing

Send invoices straight from your billing system and let us handle professional printing and delivery via Royal Mail.Learn more

Bulk mail

Send large batches of letters through the API and have them printed and posted automatically, no matter the volume.Learn more

Mail merge

Upload your documents and recipient data, we print, personalise and post each letter via Royal Mail on your behalf.Learn more

Use cases by industry

Built for the way your industry already sends mail

Automate the statements, notices and reminders clients expect to receive by post, straight from your existing systems.

Account statements

Keep clients informed with regular summaries of account balances, transactions and interest earned.

Loan & mortgage statements

Send detailed updates on loan and mortgage balances, rates and repayment schedules.

Credit card statements

Post credit card statements to boost attention and increase the likelihood of timely payment.

Tax return statements

Deliver printed tax return statements by mail to add tangible value and strengthen client trust.

Contract and policy updates

Notify clients by post about important changes to contracts, policies or general terms.

KYC verifications

Use postal letters to verify client addresses as part of your Know Your Customer procedures.

Application forms

Send application forms by post so clients can complete them without needing a printer.

Payment reminders

Trigger automated letters for due payments or reactivations to reduce late fees and missed deadlines.

LetterAPI supports countless other financial use cases and ensures reliable postal communication.

LetterAPI is also perfect to

Replace franking machines

Ditch bulky franking machines and fully digitise your entire outgoing mail process.

Switch to hybrid mail

Reduce manual processes and improve flexibility with an API-first approach to postal mail.

Handle output management

Streamline your output management with a scalable, high-performance infrastructure.

Returns processing

Automated return mail handling, with notifications the moment a letter can't be delivered.

Pricing

Transparent, pay-per-letter pricing with no fixed contracts or monthly subscriptions.

Integrations

Ready-to-use integrations to send letters straight from your existing workflows.

Start sending letters online today

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LetterAPIPrint and post letters in the UK, from one letter to thousands.