IRP error 2177: Unit code is not in the master
What the IRP says
{0}, {1} and so on stand for the values the IRP fills in.
Why it happens, in NIC's words
Invalid unit code has been passed
What NIC says to do
Please pass the correct unit code as per the master provided for e-invoice. Check the correct unit code in the portal under Search -> Master codes. If the unit code is not matching with your required unit, you may have to convert unit to one existing in the master list of unit code.
NIC's wording, from its published list of IRP errors, as read on 1 October 2026.
In plain words
The unit on a goods line is not one of the unit codes (UQC) in the IRP's unit list.
How to fix it
- Replace the unit with the code from the GST unit list, written as the list prints it: for example NOS (numbers), KGS (kilograms), MTR (metres) or CBM (cubic metres).
- If your unit is not in the list, NIC says to convert the quantity to a unit that is.
Can you catch it before you upload?
Yes. The free pre-check on this site tests for it before you upload. It checks the unit on each goods line against the unit list that GSTN publishes.
Free, with no sign-up. The file is checked in your browser and never leaves it. A clean result does not mean the IRP will accept the invoice.