TaxCompliance

4 Days Left: Beware of These Common Last-Minute Errors

Siam Advice FirmTax Analysis

We are in the danger zone for human error. When investors rush through the portal in the final days of March, three specific mistakes happen more than any others.

 

1. Wrong Tax ID for Deductions

Whether it is your life insurance provider or the school you donated to, ensure the 13-digit Tax ID you enter for the deduction matches the receipt exactly. The e-Filing system uses this ID to cross-verify the expense.

 

2. Incomplete Document Uploads

The portal requires specific PDF formats for supporting documents. If you upload a blurry photo or a password-protected PDF, an auditor will inevitably reject it and ask for a resubmission, which delays your processing by weeks.

 

3. Selecting the Wrong Tax Year

It sounds simple, but every year people accidentally start a "New Filing" for the wrong year (e.g., 2026 instead of 2025). Double-check the header of every screen. You are filing for income earned between January 1 and December 31, 2025.

 

Stay Calm

Slow down. Spend five extra minutes reviewing each field before clicking 'Submit'. Those five minutes today save five hours of future headache with the Revenue Department.

 


Related Service: Accounting & Tax Compliance — Professional review to catch common filing mistakes before submission.

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