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How do I submit an ITR12 after receiving an auto-assessment?
How do I submit an ITR12 after receiving an auto-assessment?
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Direct answer
Submit an ITR12 after an auto-assessment only if you do not agree with it or it is incomplete. SARS says you can complete and file the return through eFiling or the SARS MobiApp. If a prepopulated item is wrong, first ask the employer, bank, medical scheme, retirement fund or other provider to correct the data it supplied to SARS.
For the 2026 filing season, non-provisional taxpayers must submit by 23 October 2026, and provisional taxpayers by 22 January 2027.
What this means in practice
An auto-assessment is based on third-party information. SARS says no ITR12 is needed when it is correct. Filing a return is the route for a taxpayer who does not agree, not a routine response to every auto-assessment message.
Do not overwrite prepopulated certificate data yourself. SARS says the individual must ask the source institution to correct the information it gave SARS. After the source says it corrected and filed the data, return to eFiling or MobiApp, check that the entry is updated and then complete the ITR12.
The deadline depends on taxpayer type. The 2026 dates above apply to the relevant individual filing season. Do not assume that the later provisional deadline applies if you are a non-provisional taxpayer.
Step-by-step
- Review the auto-assessment and records.
Open the ITA34 through eFiling or the MobiApp. Compare it with the documents for the same year, including income certificates, medical and retirement records and deduction evidence.
- Identify the reason you do not agree.
Record missing income, an incorrect certificate, a missing deduction or another factual difference. Keep the source document that supports the point.
- Correct third-party data at source.
Ask the employer, fund, bank, medical scheme or other relevant institution to correct its record with SARS. Retain confirmation of the request and the correction.
- Open the ITR12 again.
Once the provider confirms that the data was corrected and filed, check the updated prepopulated information. Do not rely on an informal assurance without checking what SARS shows.
- Complete and submit the return.
Use eFiling or the SARS MobiApp, complete the required sections truthfully, review the declaration and submit. Save the submission proof and later assessment notice.
- Keep supporting documents.
Keep the ITA34, certificates, correction records and documents supporting the return. SARS may ask for evidence after submission.
Documents and records to keep
- Auto-assessment ITA34.
- IRP5 or IT3(a), investment, medical and retirement certificates.
- Source correction correspondence.
- Supporting records for deductions and other income.
- ITR12 submission confirmation and later ITA34.
Important limits and exceptions
Do not file an ITR12 when the auto-assessment is complete and correct merely because you received a notification. Conversely, do not accept it when material information is missing just to avoid filing.
This guide covers filing after auto-assessment, not a formal objection or appeal. It does not calculate a refund, a balance payable or a personal tax result. A source correction can be necessary before the return accurately reflects the information supplied to SARS.
If the return is complex, the records are missing or there is an active verification issue, take advice before submitting a position you cannot support.
When to get tailored advice
Get help with multiple income sources, business or foreign income, complex deductions, missing certificates or a material difference on the assessment. TaxProof can help organise documents and a filing checklist. SARS and the third-party provider control the assessment data and correction process.
Related TaxProof guides
- Submit a tax return in South Africa
- How do I correct or reject a SARS auto-assessment? (B03-ADM-006)