IRS Form 8879 is the e-file signature authorization form. Before a tax preparer can electronically file a taxpayer’s return, the taxpayer must sign Form 8879 confirming the information on the return. Form 8879 is the most important e-signature workflow in accounting client portals.
The IRS requires that e-signatures on Form 8879 be supported by Knowledge-Based Authentication (KBA) for remote signing. Major accounting portals (TaxDome, Canopy, Karbon, Liscio) handle this natively.