Gather the PDFs in Files
Place the documents somewhere easy to find in the Files picker. Give them recognizable names if several files look alike.
Use Safari and the Files app
Merge PDFs on an iPhone
If several PDFs in the Files app need to become one attachment, you can merge them in Safari without moving to a desktop computer or creating an account.
Open Merge PDF →Choose and arrange them
Open Merge PDF in Safari, select two or more PDFs, and put them in final reading order. File order is important because the tool joins whole documents sequentially.
Download and check the result
Open the merged PDF from Downloads or Files. Check the first and last page of each source section so you know nothing is missing or reversed.
Phone memory is the practical limit
Large PDFs and many-page image scans can use significant memory. If processing stops, close other Safari tabs or merge smaller groups first.
Before you finish
Before selecting files, rename look-alike documents in Files so their purpose is obvious—for example, form-signed.pdf and supporting-statement.pdf. This reduces the chance of merging the wrong revision. If a website has a file-size limit for the final upload, check that limit before assembling a very large packet because merging does not automatically compress the result.
Questions about this task
Do I need an iPhone app?
No. The tool runs in Safari.
Can I merge password-protected PDFs?
They generally need to be unlocked first.
Are the PDFs uploaded?
The supported merge operation runs in your browser rather than sending document contents to BetterThanPDF.