The short answer
MEPCO's official online bill portal does not offer a CNIC-based bill lookup. The lookup form accepts a 14-digit reference number or a 10-digit Customer ID — there is no CNIC field. Any website that promises "MEPCO bill check by CNIC" and shows you a bill is either mistaken or not what it claims to be.
Why not? One CNIC can hold multiple electricity connections (home, shop, tube-well), so a CNIC alone cannot identify which bill you want.
What to do if you only have your CNIC
1
Check any old bill, receipt or payment SMS — the reference number appears on all of them, and in bank/wallet payment history under "MEPCO".
2
Visit your MEPCO sub-division office with your original CNIC; staff can look up your connection and give you the reference number.
3
Call helpline 118 — they can guide you to your sub-division office or complaint cell.
4
Once you have it, save it. The number never changes — store it in your phone so you never need the CNIC route again.
A note on privacy
Because bills are looked up by reference number (not CNIC), anyone holding your reference number can view your bill. Treat it like a semi-private number: share it only with people who pay your bill, and be cautious of websites that ask for your CNIC and reference number together.