Tax-practice glossary

Plain-English definitions for the terms preparers run into around e-filing and e-signing — each one points to the IRS, NIST, or FTC source behind it.

Glossary

EFIN (Electronic Filing Identification Number)

The number the IRS issues after the e-file application and suitability check.

 Glossary

PTIN (Preparer Tax Identification Number)

The number every paid preparer must hold and renew every year.

 Glossary

KBA (Knowledge-Based Authentication)

Question-based identity verification for remote Form 8879 signing under Pub 1345.

 Glossary

IAL2 (Identity Assurance Level 2)

NIST SP 800-63A's ID-plus-selfie identity assurance level, an alternative to KBA.

 Glossary

Form 8879 (IRS e-file Signature Authorization)

The IRS e-file Signature Authorization every e-filed return needs on file.

 Glossary

WISP (Written Information Security Plan)

The written security plan the FTC Safeguards Rule requires, built from IRS Pub 5708.

 Glossary

IRS Publication 1345

The e-file provider handbook behind the 8879 and identity-verification rules.

Looking for ready-to-use paperwork instead of definitions? See the template library.

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