Bulk personalised letters as PDF

When a PDF mail merge beats a word-processor merge

Word’s mail merge is great when the letter itself lives in Word. It gets awkward when your letterhead came from a designer as a PDF, when the layout shifts depending on which computer opens the file, or when you need a separate PDF for every recipient; that usually means macros or a paid add-on. Here the letterhead stays exactly as designed, because the tool only adds text on top of your PDF, and each letter can be saved as its own named file.

Writing the letter with placeholders

A placeholder is a column name in double curly brackets. {{Amount}} becomes “£50.00” for one supporter and “£120.00” for the next. You can mix placeholders and ordinary text freely inside one text box.

• Body paragraphs: use one text box with “Wrap onto multiple lines” switched on and type the whole paragraph, placeholders included: “Thank you for your gift of {{Amount}} to our {{Campaign}} appeal.” The text reflows for each person, so longer names and amounts are no problem. Press Enter twice to start a new paragraph.
• Greetings: Dear {{First Name|friend}}, prints “Dear friend,” whenever the First Name cell is empty, which avoids the dreaded “Dear ,”.
• Address blocks: one left-aligned text box with a line per field: {{Name}}, {{Address}}, {{Town}}, {{Postcode}}. If some addresses have an extra line and others don’t, build the whole block in the spreadsheet with =TEXTJOIN(CHAR(10),TRUE,B2:E2). It skips empty cells, and the line breaks carry through into the letter.
• The date: a text box with plain text such as “20 March 2026” is enough. Change it once and every letter updates.

Letters that work well this way

• Donation receipts and thank-you letters for charities and clubs
• Membership renewals and subscription reminders
• School letters to parents naming each pupil and their class
• Rent reviews and notices to tenants
• Price-change or policy notices to customers
• Offer letters, confirmations of employment and reference letters

Because the merge runs on your own device, it also suits letters containing personal information such as amounts, addresses or reference numbers. Nothing is sent to a server to be processed.

Layout tips

• Window envelopes. Measure where the window sits and put the address box there using the “Exact position” fields in the text box panel. Positions are in points: 72 points = 1 inch = 25.4 mm. Print one test letter, fold it and check before printing the batch.
• Readable body text. 10–12 pt, left aligned, in the same font as your letterhead if you have its .ttf or .otf file. Justified text isn’t supported; ragged-right text is easier to read anyway.
• Leave space for the longest paragraph. Text boxes don’t flow onto the next page. Preview the row with the most text before generating, and keep your sign-off low enough on the page that it never overlaps.
• Double-sided printing. If the letter has a second page, use the combined PDF and a template with an even number of pages so every letter starts on a fresh sheet.

Questions about letters

Making certificates instead? Try the certificate generator. Filling an existing form? See fill a PDF form from CSV, or go back to the main PDF mail merge tool.