Checkpoint 7 of 7

Test edge cases

The trouble starts on the day you issue your first credit note, multi-currency line, or partial invoice. Run these scenarios in the pilot — find the breaks before the FTA does.

Standard tax invoice

Why test it

Every B2B invoice you issue. This is the foundation — every other test depends on it.

What can break

Missing TRN, wrong tax rate, line totals don't sum to the header total.

Credit / debit note

Why test it

A customer returns goods, you apply a discount after invoicing, or you correct a billing error.

What can break

Broken IRN reference to the original, sign errors (positive amounts), tax not reversed.

Mixed-rate invoice

Why test it

One invoice has lines at standard 5%, zero-rated 0%, and exempt — common in services + exports.

What can break

Default 5% VAT silently applied to zero-rated or exempt lines.

Reverse charge

Why test it

You buy services from a non-resident supplier (SaaS, consulting). You self-account for VAT, not them.

What can break

VAT charged twice — once by supplier, once on your VAT return.

Multi-currency

Why test it

You bill a customer in USD or EUR but VAT must be reported in AED using the FTA's daily rate.

What can break

Bank exchange rate used instead of the FTA's published rate — invoice rejected on validation.

Partial / milestone

Why test it

Long contracts billed in stages — construction, consulting, software implementation.

What can break

VAT applied to the full contract value instead of just the milestone being invoiced.

Designated zone supply

Why test it

You sell goods to a customer in DAFZA, JAFZA, or any Designated Zone — treated as outside the UAE for VAT.

What can break

Standard 5% VAT applied because the system reads the address as mainland Dubai.

Rejection & correction

Why test it

The buyer's ASP rejects your invoice — wrong TRN, validation error, missing required field.

What can break

Silent failures — your system thinks the invoice sent. The buyer never received it. Cash flow disappears.