Most rejected eTIMS invoices aren’t caused by the integration itself. They come from master data that was never set up with tax validation in mind. Before switching on eTIMS, check these.
1. Item classification
Every item you sell needs the right KRA item classification and the correct tax type. Items created years ago by different people are usually the first problem.
2. Customer PINs
Business customers need a valid PIN on the customer record. Clean this up in bulk before go-live rather than invoice by invoice afterwards.
3. Units of measure and packaging
Your units need to map to the codes KRA expects. “Pcs”, “PCS” and “Pieces” in the same system will cause trouble.
4. Credit notes and returns
Credit notes must reference the original validated invoice. Make sure your returns process always starts from the invoice — not from a blank credit note.
5. A failure plan
Decide what happens when validation fails: who gets alerted, how the invoice is retried and how you keep trading. Test it before you need it.