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How do I fix an "invalid tax number" when issuing a Section 18A?

In short: A South African SARS income-tax (tax reference) number must be exactly 10 digits, start with 0, 1, 2, 3 or 9, and pass the checksum. If ActiveDonor shows an invalid tax number error, open the donor's tax information, retype the correct number with no spaces or dashes, and save.

The rule

A valid SA tax reference / SARS number is:

  • exactly 10 digits;
  • starts with 0, 1, 2, 3 or 9;
  • passes the Luhn checksum; and
  • is not all zeros.

The error tells you exactly what's wrong, for example Invalid Income tax number: Must be exactly 10 digits., …Must start with 0, 1, 2, 3 or 9., or …Failed validation check. A foreign (non-SA) tax number that isn't in this format is also rejected — a donor needs a valid SA tax number for a Section 18A certificate.

How to fix it

  1. In the top navigation bar, click Donors and open the donor.
  2. Open the donor's tax/ID information panel (Update Tax Information for {donor name}).
  3. In the Tax Number field, enter the 10-digit number exactly as it appears on the SARS notice of registration — no spaces, dashes or the entity name.
  4. (Optional) Tick Update all Section 18A with above info. so the correction flows onto certificates already issued.
  5. Click Save (or Update).

On success you'll see Donor tax info has been udpated. If it's still wrong, the red message naming the specific problem reappears next to the field.