Advance tax and self-assessment tax are both payments you make yourself to the Income Tax Department, but they serve different purposes at different points in the year. Advance tax is paid in four installments during the financial year, based on your estimated income, and is triggered when your tax liability after TDS and TCS exceeds ₹10,000. Self-assessment tax is the balancing payment you make after the financial year ends, once you know your actual income, to clear whatever is still owed before you file your return.
Getting the two mixed up, or skipping advance tax and hoping to settle everything as self-assessment tax later, is one of the more expensive mistakes an Indian taxpayer can make. Separate interest provisions under the Income Tax Act apply to each, and they can stack.
The Core Difference
Advance tax exists so the government collects revenue as you earn it rather than waiting for a single lump sum at year-end. The Income Tax Department calls it a “pay-as-you-earn” scheme.1Income Tax Department. Schedule IT – Details of Advance Tax and Self-Assessment Tax You estimate your total income for the year, work out the tax, subtract TDS and TCS already deducted, and pay the balance in four quarterly installments.
Self-assessment tax is the cleanup. After March 31, when you know exactly what you earned, you calculate your actual liability and subtract everything already paid: TDS, TCS, advance tax installments, and any relief under sections 90 or 91 for foreign taxes. Whatever remains is your self-assessment tax, and Section 140A requires you to pay it before filing your return.2Income Tax Department. Income Tax Act Section 140A
A few practical distinctions follow from this:
- Timing: Advance tax is paid during the financial year on June 15, September 15, December 15, and March 15. Self-assessment tax is paid after the year ends, before you file.
- Basis: Advance tax uses estimated income. Self-assessment tax uses actual, finalized income.
- Who pays: Advance tax mainly catches business owners, freelancers, and professionals whose income isn’t fully covered by TDS, plus salaried people with meaningful side income. Self-assessment tax applies to almost anyone filing a return who still has a balance due.
- Challan code: On Challan ITNS 280, advance tax is minor head 100, self-assessment tax is minor head 300.
If you pay accurate advance tax through the year, your self-assessment tax will be near zero. A large self-assessment payment usually signals that advance tax was underpaid, and that is exactly when interest charges pile up.
When You Owe Advance Tax
Section 208 sets the threshold: advance tax is payable when your estimated tax liability for the year, after accounting for TDS and TCS, comes to ₹10,000 or more.3Income Tax Department. Income Tax Act Section 208
Business owners, freelancers, and professionals almost always cross this line because their income isn’t subject to regular TDS in the way a salary is. Salaried employees aren’t automatically exempt either. Significant rental income, capital gains, or interest income beyond what TDS covers can push you over the threshold.
Because the payment is based on estimates, you can adjust later installments up or down as your income picture changes. That flexibility is deliberate, but the interest rules assume you will use it.
The Advance Tax Installment Schedule
Section 211 sets four deadlines, each expressed as a cumulative percentage of your total estimated advance tax for the year:4Income Tax Department. Income Tax Act Section 211
- June 15: At least 15% of the total.
- September 15: At least 45%, minus what you paid in June.
- December 15: At least 75%, minus earlier payments.
- March 15: The full 100%, minus everything paid so far.
These are cumulative, not standalone. Miss June entirely and you need to reach the full 45% by September to be on track, and you will still owe interest on the June shortfall.
Presumptive Taxation Simplification
If you have opted for the presumptive taxation scheme under Section 44AD (small businesses) or Section 44ADA (professionals), the quarterly schedule doesn’t apply. You can pay the entire advance tax in a single installment on or before March 15 of the financial year.5Income Tax Department. Small Businessmen – Benefits Allowable
Capital Gains and Sudden Income
You can’t estimate in June a capital gain that arrives in November. If such income arises after an installment deadline has passed, you’re expected to pay advance tax on it in the remaining installments. You won’t face 234C interest for earlier quarters in which the income didn’t yet exist.
When You Owe Self-Assessment Tax
Self-assessment tax must be paid before you submit your return, and Section 140A makes this non-negotiable: you cannot file with an unpaid balance and sort it out afterward. The return must be accompanied by proof that you have paid the full amount, including any interest owed under sections 234A, 234B, or 234C.2Income Tax Department. Income Tax Act Section 140A
Because the payment is tied to filing, your deadline is your return deadline. For Assessment Year 2026-27 (income earned in FY 2025-26), the standard due date for most individual taxpayers filing ITR-1 or ITR-2 is July 31, 2026.6Press Information Bureau. 15 September 2025 ITR Deadline What Every Taxpayer Should Know Taxpayers whose accounts require a tax audit generally have until October 31.
CBDT sometimes extends filing deadlines. The AY 2025-26 individual deadline was pushed from July 31 to September 15, 2025. Don’t count on it. And an extension to file is not an extension to pay: Section 234A interest starts running from the day after the original due date, so delaying payment until an extended deadline still accumulates interest.
One detail catches people out. When a self-assessment payment falls short of covering both tax and interest, the amount is applied to fees first, then interest, and only then to the actual tax. A partial payment may not reduce your core tax debt at all.
Who Doesn’t Have to Pay Advance Tax
Two exemptions matter.
The ₹10,000 threshold is the first. If your total tax liability after TDS and TCS is below that for the year, you owe no advance tax and simply settle up as self-assessment tax when you file.3Income Tax Department. Income Tax Act Section 208
The second is often missed. Section 207 exempts resident senior citizens who don’t have income from business or profession. If you are 60 or older, resident in India, and your income comes entirely from pensions, interest, rent, or capital gains, you are free from advance tax obligations. Interest under sections 234B and 234C won’t apply to you either.7Income Tax Department. Senior Citizens and Super Senior Citizens for AY 2026-2027 You still owe the tax, but you pay it all as self-assessment tax before filing.
What It Costs to Get It Wrong
Three interest provisions can apply, and they can stack on the same taxpayer for the same year.
Section 234B: Default in Paying Advance Tax
Section 234B applies if you didn’t pay advance tax at all or paid less than 90% of your assessed tax for the year. You’re charged simple interest at 1% per month, or part of a month, on the shortfall. The interest runs from April 1 following the financial year until your total income is determined through assessment.8Income Tax Department. Income Tax Act Section 234B Assessed tax here means total tax minus TDS and TCS, so even a modest shortfall below the 90% mark triggers months of compounding interest.
Section 234C: Deferment of Installments
Even if you pay enough advance tax overall, you can still owe 234C interest for being late on individual installments. Each quarter is measured separately. If you paid less than 15% by June 15, less than 45% by September 15, or less than 75% by December 15, you owe 1% per month for three months on that quarter’s shortfall. For the March 15 installment, interest runs from the shortfall date until you actually pay. Taxpayers who dump all their advance tax into the final quarter get caught here.
Section 234A: Late Filing
Section 234A charges simple interest at 1% per month on unpaid tax if you file your return after the due date. The clock starts the day after the deadline and runs until you file. The amount subject to interest is your total tax liability minus advance tax, TDS, TCS, and any self-assessment tax paid before the due date.9Income Tax Department. Interest and Fees
Put simply: 234B and 234C punish you for not paying enough during the year. 234A punishes you for not settling up on time afterward. A taxpayer who skips advance tax and then files late can face all three at once, each calculated on a different base amount over a different time window.
How to Pay Each One
Both payments go through the same Challan ITNS 280 on the Income Tax Department’s e-filing portal. The critical choice is the minor head:
- Minor head 100 for advance tax.
- Minor head 300 for self-assessment tax.
The major head for individuals is 0021 (Income Tax Other Than Companies). Selecting the wrong minor head doesn’t lose your money but creates mismatches in your tax records that have to be corrected later. Getting the assessment year wrong is the other easy trap: for income earned in FY 2025-26, the assessment year is 2026-27. A mismatch parks your payment in the wrong year’s ledger, and correcting it requires a formal request to the assessing officer.
After paying, save the receipt. The BSR code, challan serial number, and payment date together form the Challan Identification Number (CIN), which you’ll need when filing your return.10Tax Information Network. OLTAS Challan Status Inquiry
To confirm the payment was recorded, check your Annual Information Statement (AIS) on the e-filing portal. From AY 2023-24 onward, Form 26AS on the TRACES portal shows only TDS and TCS data, so it will not reflect your advance tax or self-assessment tax payments.11Income Tax Department. FAQs on AIS (Annual Information Statement) Payments usually take a few business days to appear. If yours doesn’t show up after a week, trace it through the OLTAS challan status inquiry before filing.
Mistakes That Cost Money
The most expensive error is also the most common: ignoring advance tax entirely and paying everything as self-assessment tax before filing. The full amount does get paid before the return deadline, but Section 234B interest has been running since April 1, and 234C interest accrued at each missed quarterly deadline. Clearing the principal doesn’t erase the interest that built up along the way.
The second is underestimating income early and never adjusting. If your September 15 payment was based on a conservative estimate but your income spiked in Q3, the December and March installments have to reflect the higher number. Honest underestimation for earlier quarters isn’t punished; failing to catch up once you know the real figures is.
The third is the assessment year on the challan. Paying advance tax in March 2026 for income earned in FY 2025-26 means selecting AY 2026-27. A wrong selection is easy to make and slow to fix.