Official forms to fill out and sign on iPhone

How we test a form

We download the official PDF from the agency website, open it in Marquo, fill every field we can, tick the checkboxes and export it with locked fields. Then we check that the values are on the page and no editable fields remain, and export once more with editable fields to check that another PDF reader can read the values. A form counts as tested only when this run is recorded in our project log with a date.

Forms we tested

Form W-9 (Request for Taxpayer Identification Number and Certification) from the IRS, revision March 2024, tested in Marquo 1.0 on October 26, 2026. All 23 fields were found; typed values and a checkbox were exported correctly. The IRS still lists the March 2024 revision as current on October 30, 2026. Read about it on the IRS Form W-9 page. Marquo does not send the form, does not check your TIN, and is not tax advice. We have not checked IRS rules on signing a W-9 electronically, so ask the requester.

Forms not tested yet

These forms are official PDFs that people are often asked to fill out. We list them so you can find the source, but we have not run them in Marquo yet. Field counts will appear after a recorded run.

Before you sign any official form, read the agency instructions. Some forms have rules about who signs, when and how they are submitted, and those rules come from the agency, not from the app. For fields and flat forms in general, see How to fill out a PDF form on iPhone.

Guides

• Fill out a PDF formForms with fields and flat scans, AutoFill, and the W-9 test.
• Sign a PDFBuilt-in Markup, Marquo and the browser tool, step by step.
• Electronic signatureImage of a signature versus a certificate-based digital signature.