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Guide · updated 1 Nov 2026

RELIEF says my DAT file has invalid characters. How to fix it.

Letters, numbers and spaces. That is the whole rule for names and addresses.

When a RELIEF purchases or sales file will not validate, the cause is very often a name or address with a symbol in it: a dot, a slash, an ampersand.

From our own filings. We make SLSP files for our own company and clients. RELIEF passed them with “No errors encountered” only after names and addresses were cleaned to the rules below. Your RELIEF version may differ, so always run the BIR’s validation module as the final check.

The rules we use

  • Only A to Z, 0 to 9 and spaces. Everything else goes.
  • Capital letters.
  • & becomes AND, and # becomes NO.
  • . ' and / are simply removed. Other symbols become a space.
  • Extra spaces are squeezed to one.
  • A name is at most 50 characters. An address is two lines of at most 30.

Before and after

As printedIn the file
ACME & SONS, INC.ACME AND SONS INC
STRONG MEDIACORP GROUP INC.STRONG MEDIACORP GROUP INC
G/F 21 STA. ISABEL ST.GF 21 STA ISABEL ST
UNIT #4 ORTÍGAS AVE.UNIT NO 4 ORTIGAS AVE
12 FOLDS PH CORP. (RESTAURANT)12 FOLDS PH CORP RESTAURANT

Find the exact line in seconds

  1. Open the free file checker.
  2. Drop in your DAT file. Nothing is uploaded; it is read in your browser.
  3. Every line with a bad character is listed, with the line number and the offending text.
  4. Fix the source list, make the file again, drop it in once more.

The same checker also catches header totals that do not match the lines, a file name whose TIN is not the one inside, and TINs that are not nine digits.

Why it happens

Receipts print names with dots, slashes and ampersands, and a free AI that reads receipt photos will copy them faithfully. The fix is not to read less carefully but to clean once, in one place, before the file is made. ClockIN does this step for you when it makes the DAT file.

Questions

Does RELIEF accept commas in a name?

We remove them. Fields in the file are separated by commas, so a comma inside a name is a risk we never take.

Do lower-case letters pass?

We write everything in capitals, the way the files that passed were written.

Will cleaning the name change what the BIR sees?

The file holds the cleaned name. The receipt keeps its own spelling; the TIN is what identifies the supplier.

Skip the hard part

Photograph the papers. ClockIN checks every line and makes the files.

Made by ClockIN, by Strong Media Corp, Metro Manila. ClockIN is not BIR-accredited. Test every file in the BIR’s own validation module before you submit it; the filing stays with you and your accountant. Rules and rates change, so confirm against the BIR’s current issuances.