Match challans against deductions

Every TDS deduction must have a corresponding challan showing the tax was deposited. The TDS return cannot be filed until every deduction is challan-matched.

Import challans from OLTAS

TDS → Challans → Import from OLTAS

ThynkTax queries the OLTAS (Online Tax Accounting System) API:

• Filters by your TAN + the period
• Returns every challan with CIN (Challan Identification Number)
• One-click bulk import

Alternatively, paste a CSV from your bank's tax-payment portal.

Auto-match

ThynkTax matches by:

• Section (e.g. 192, 194A, 194C)
• Amount (rounded to nearest rupee)
• Period (the month of the deduction)

Match types:

• Exact - challan amount = sum of deductions for the section + period
• Partial - challan covers some but not all deductions (split across multiple challans)
• Excess - challan amount > deductions (rare; flag for review)
• Missing - deduction exists but no challan covers it (must be deposited)

Resolve mismatches

For partial matches, manually allocate one challan across multiple deductions.

For missing matches, generate a challan template (Section 281, code 1020/1030/1040/etc.) and pay via the income tax portal. Once OLTAS reflects it (typically 24-48 hours), re-import.

Section 201 interest

If a deduction is matched to a late-deposited challan, ThynkTax computes Section 201 interest (1.5% per month from deduction date to deposit date) and surfaces it in the TDS return prep.