Section 234B & 234C · Income-tax Act, 1961 · 1% Per Month Simple Interest

Advance Tax Shortfall & Interest Calculator

Compute quarterly instalment shortfall interest under Section 234C (June 15, Sept 15, Dec 15, March 15) and default interest under Section 234B.

Statutory Summary (AI Overview)

Under Section 234C of the Income-tax Act, advance tax must be paid in four instalments: 15% by June 15, 45% by September 15, 75% by December 15, and 100% by March 15. Shortfall attracts 1% simple interest per month for 3 months per instalment (1 month for Q4). Additionally, if total advance tax paid before March 31 is less than 90% of assessed tax, Section 234B imposes 1% monthly interest from April 1 of the assessment year.

Input Assessed Tax & Instalment Payments

Net Assessed Tax (Tax minus TDS/TCS) (₹)

Q1: Paid by 15th June (Target 15%)

Shortfall: ₹20,000

Q2: Cumulative Paid by 15th Sept (Target 45%)

Shortfall: ₹30,000

Q3: Cumulative Paid by 15th Dec (Target 75%)

Shortfall: ₹30,000

Q4: Cumulative Paid by 15th March (Target 100%)

Shortfall: ₹30,000

Advance Tax Interest Summary Sec 234B & 234C Payable

Sec 234C Interest

₹2,700

Instalment deferment

Sec 234B Interest

₹300 / mo

Paid < 90% assessed tax

Total Interest

₹3,000

Compounded under IT Act

Automate Advance Tax Estimation & Client Nudges

CORS automatically tracks the 4 advance tax quarterly cycles (June 15, Sept 15, Dec 15, March 15) and sends computation reminder links to your clients.

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