MergeNinja

Mail merge for QuickBooks, Stripe & Excel

Turn your QuickBooks or Stripe data into a personalized Word document for every customer.

Connect QuickBooks Online or Stripe (read-only), or upload an Excel file. Add a Word template with merge fields. MergeNinja fills it in for every customer (dunning letters, year-end statements, receipts, renewal notices) and emails you the finished batch.

7 days free · no card to start

app.mergeninja.com

Synced invoices

CustomerOpenDays
Acme Landscaping $1,240.00 45
Harbor Dental $385.50 31
Bluebird Cafe $92.75 12

Dear Acme Landscaping,

Our records show an open balance of $1,240.00, now 45 days past due…

× 200 customers, one click

MergeNinja merges synced invoice data into a Word letter for every customer at once.

How it works

Three steps the first time. One click every time after.

  1. 1

    Connect your data

    Connect QuickBooks Online or Stripe with read-only access, or upload an Excel file. No exports, no CSV cleanup.

  2. 2

    Upload a Word template

    Bring your own .docx with merge fields: your fonts, your logo, your layout. If you can use Word, you already know how.

  3. 3

    Sync, filter, merge

    Sync your live data, filter it (say, open + past due), and merge. Finished documents arrive by email, ready to send or print.

The statement run, without the afternoon.

You know the routine. Export, clean up, wrestle Word's merge wizard, and repeat it every single month.

The old way, every month

  1. 1 Export CSV
  2. 2 Fix columns
  3. 3 Fight the merge wizard

…then do it all again next month, with a stale export.

With MergeNinja

  1. 1 Connect
  2. 2 Pick template
  3. 3 Merge

Set up once. The second run is one click.

ChatGPT writes a letter. MergeNinja writes it for all 200 customers, with the right names, amounts, and days overdue.

Who uses MergeNinja

Anyone whose customers expect documents, not just emails.

Trusted by bookkeepers and small businesses.

QuickBooks Online Stripe Excel

Read-only connections: we can see your data, never change it.

Read-only & encrypted

We can see your data, never change it. OAuth tokens are encrypted at rest, and disconnecting revokes access at QuickBooks and Stripe too.

Security details →

Your own .docx, your formatting

It's your Word template: fonts, logo, and layout stay exactly as you built them. We only fill the merge fields.

Compare with manual merges →

Set up once, re-run monthly

Your template stays put and the data refreshes itself. The second run, and every run after, is one click.

One plan. Every document type.

No tiers to decode. $45 a month for unlimited merges across QuickBooks, Stripe, and Excel, and one recovered overdue invoice typically covers a year.

Full pricing details →

MergeNinja Standard

$45 / month

  • 7-day free trial: no card to start
  • Unlimited mail merges
  • QuickBooks Online, Stripe, and Excel data sources
  • All document types: letters, statements, receipts, notices

7 days free · no card to start

Stop exporting. Start merging.

Connect your data, upload your Word template, and send every customer document in one click.

Start free trial

7 days free · no card to start