Tax return redaction is the removal of taxpayer data from a self-assessment filing whose confidentiality is protected under CRCA 2005 s.18. That section binds HMRC officers not to disclose a taxpayer's identity or figures. anonym.plus marks each identifier on your device, so the form reads cleanly while protected data goes.
When this applies
An SA100 states the filer's National Insurance number, UTR, address, and income on the first pages. You strip that protected information before the copy leaves your office.
How anonym.plus handles it
- Open the filing in anonym.plus on your device.
- Built-in OCR reads a scanned or printed copy.
- The app marks the NI number, UTR, name, and address.
- Confirm each marking and keep the line totals.
- Mask the NI number or swap it for a label.
- Save the clean copy locally.
What you need to provide
- The filing (PDF, scan, or DOCX).
- An operator: Mask keeps only the suffix of an NI number.
- Optional allow-list for the tax year you must cite.
PII & financial identifiers detected
| Category | anonym.plus entity type | Example |
|---|---|---|
| Identifiers | UK_NINO | QQ 12 34 56 C → QQ XX XX XX C |
| Tax reference | NATIONAL_ID | UTR 10 digits → [UTR] |
| Names | PERSON | filer Daniel Rowe → [TAXPAYER] |
| Location | LOCATION | 44 Elm Street, Bath → [ADDRESS] |
| Money | MONEY | repayment £2,310 → [AMOUNT] |
| Dates | DATE_TIME | date of birth 1979 → [DOB] |
Compliance achieved
- Reflects the confidentiality duty in CRCA 2005 s.18.
- Masks the NI number and UTR, the core of a filer's identity.
- Offline work keeps protected data off any server.
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Limitations & cautions
Section 18 binds officials, yet a shared copy can still expose a filer. The app marks named items; a unique figure may hint at one person. Review the supplementary pages before you share.
Frequently asked questions
What does CRCA 2005 s.18 protect?
It bars HMRC officers from disclosing taxpayer information — identity, the figures filed, and data held. anonym.plus marks those identifiers so a copy you share carries the same care.
How much of the NI number may stay?
Often only the final letter, depending on the recipient. The Mask operator keeps the suffix and hides the digits in one pass.
Is the copy sent to a server?
No. The app is fully offline. The filing and its data never leave your device.