Tax Twin India: Old vs New Regime With Share Sales, Card by Card (2026-27)

Open Tax Twin →

You are salaried, you sold some shares or equity mutual fund units this year, and you want to know your tax under both regimes before 31 March. By the end of this guide you will be able to fill the four cards in Tax Twin, read the Old and New regimes side by side, understand the capital gains table, and use the year-end moves and the PDF. Treat everything here as general information and check your own case with a practising CA.

What does Tax Twin do that a regime calculator does not?

Tax Twin is a tax planner for one tax year. You enter salary, interest, dividends and listed share or equity fund sales once, and it taxes the same profile under the Old and New regimes, shows every step, and re-runs the calculation for a few moves you could still make before 31 March. Outside its scope it refuses and says why.

The rules are written out on the Tax Twin methodology page and the sources page. The Act itself is the primary source. Your inputs are calculated in your browser.

Every worked example below was run through the Tax Twin engine and also through a separate reference calculation written in Python. Both gave the same figures, and they match what the page displays.

If you only have a CTC and no share sales, start with the In-Hand Salary Calculator guide. Tax Twin asks for gross salary, not CTC.

What are the five questions at the top?

The Scope Check asks five Yes/No questions before anything else:

1. Are you 60 years or older in Tax Year 2026-27?
2. Are you a Non-Resident Indian (NRI) or filing for a HUF?
3. Do you have income from business, profession, intraday equity or F&O?
4. Do you have income or losses from house property (rental or home loan interest)?
5. Did you sell real estate, gold, unlisted shares or debt mutual funds?

Answer Yes to any one and the page shows "Calculation Paused: Outside Phase 1 Scope" with the reason and, where one exists, a link to a better tool. No cards or numbers follow. That is deliberate: a number from a tool that does not cover your case is worse than no number. For business income, try the Business Income Tax Calculator and its guide. For traders, see How Trading Income Is Taxed in India.

Card 1: Salary Income

Only Annual Gross Salary is required. It opens at Rs 15,00,000 with basic at Rs 6,00,000.

• Annual Gross Salary (Rs). Before the standard deduction, and including any employer NPS. Buttons set Rs 12 lakh, Rs 15 lakh, Rs 18 lakh or Rs 25 lakh.
• Basic Salary (Rs). Sets the HRA and NPS limits. Quick-set buttons fill 40% or 50% of gross. If you leave basic empty and enter no HRA or employer NPS, it is counted as 0. With HRA or employer NPS entered, basic is required.
• Employer NPS Contribution (Rs inside Gross). Allowed up to 14% of basic in the New regime and 10% of basic in the Old regime.
• Professional Tax (Rs a year). Deducted under s.19(1) in the Old regime only.
• Annual HRA Received, Annual Rent Paid and the metro tick box. The HRA exemption applies in the Old regime only. It is the least of HRA received, rent paid less one-tenth of basic, and 50% of basic in the eight metros (Delhi, Mumbai, Kolkata, Chennai, Hyderabad, Pune, Ahmedabad, Bengaluru) or 40% elsewhere. If rent is below one-tenth of basic, the exemption is Rs 0, never negative.

Amounts must be whole rupees, with no paise and no negatives. Otherwise the page shows "Check Your Entries" instead of a result.

Card 2: Other Income

Two boxes, both optional: Total Interest Income (savings, recurring and fixed deposit interest) and Total Dividend Income. Type your yearly totals. Both are taxed at slab rates in both regimes.

Card 3: Listed Shares and Equity Mutual Funds Sold

Click Add Sale Lot for each purchase lot you sold between 1 April 2026 and 31 March 2027. A lot is one purchase, so if you bought the same share on three dates and sold part of it, you may need up to three rows. Your broker or depository statement already applies first-in-first-out (s.67(7)(c)) to decide which purchase was sold. Tax Twin does not match lots for you, so read the lots off that statement.

Each row has:

• Asset Type. Listed Equity Share or Equity-Oriented Mutual Fund.
• Purchase Date and Sale Date. The sale date must fall inside the tax year. A date outside it is refused.
• Purchase Cost (Rs). What you paid, without STT.
• Sale Value (Rs). The gross sale amount.
• Sale Expenses (Rs). Brokerage and similar charges, without STT.
• STT Paid on Sale? Must be Yes. A sale without STT is refused, because the 20% and 12.5% rates here apply only to sales on which STT was paid.
• STT Paid on Purchase? Appears for shares. A long-term share needs Yes. "No" and "Not sure" are refused for a long-term share; check your contract note.
• FMV on 31-Jan-2018 (Rs). Appears only for a long-term lot bought before 1 February 2018.
• Planned sale tick box. Tick it if the sale has not happened yet. It feeds the hold-longer move described below.

Brought-Forward Capital Losses sits under the lots: one box for short-term and one for long-term. Type the losses you carried forward from earlier years. Tax Twin takes them as your numbers and does not check that they were carried forward correctly. A loss carries forward for up to eight tax years (s.111(2) read with s.121) and only if it was determined in a return filed under s.263(1); a belated return is filed under s.263(4).

A lot is short-term if you sold it on or before the date 12 months after buying. One day later it is long-term. Short-term gains are taxed at 20% under s.196. Long-term gains are taxed at 12.5% under s.198 on the part above Rs 1,25,000.

Card 4: Old-Regime Chapter VIII Deductions

These apply only in the Old regime. The New regime allows none of them.

• Section 123 Investments (Rs). Employee PF, PPF, ELSS, life insurance and principal repayment, capped at Rs 1,50,000. Anything above is not counted.
• Own NPS Contribution (Rs). Capped at Rs 50,000 under s.124(3).
• Other Deductions Total (Rs). Health insurance, education-loan interest, donations. Used as typed and not checked.

These deductions reduce your slab income. They never reduce capital gains, and a deduction larger than slab income is lost.

Type this: Rs 15 lakh salary and one short-term sale

Keep the default Rs 15,00,000 gross and Rs 6,00,000 basic. Add one lot: Listed Equity Share, bought 2026-06-01, sold 2026-11-10, cost Rs 4,00,000, sale value Rs 5,00,000, STT on sale Yes.

The tiles read: New Regime Tax Rs 1,18,300, Old Regime Tax Rs 2,78,200, Lower Tax Option "New regime", Annual Difference Rs 1,59,900. The comparison fact reads "New regime has the lower tax by Rs 1,59,900 for the year."

Ledger line	New regime	Old regime
Net salary income	Rs 14,25,000	Rs 14,50,000
Taxable short-term gain (s.196)	Rs 1,00,000	Rs 1,00,000
Total income	Rs 15,25,000	Rs 15,50,000
Tax on slab income	Rs 93,750	Rs 2,47,500
Tax on short-term gain at 20%	Rs 20,000	Rs 20,000
Tax before surcharge	Rs 1,13,750	Rs 2,67,500
Cess (4%)	Rs 4,550	Rs 10,700
Total tax payable	Rs 1,18,300	Rs 2,78,200

Remove the lot and the same salary gives Rs 97,500 and Rs 2,57,400. The share sale added Rs 20,800 in the New regime, which is Rs 20,000 of tax on the gain plus 4% cess.

A second case shows the rebate. Gross Rs 12,75,000, salary only, no lots: New regime tax is Rs 0 and Old regime tax is Rs 1,87,200. Under the New regime, taxable income is Rs 12,00,000 and the rebate under s.156 cancels the slab tax. The Old regime has no rebate that large at that income.

How do I read the two regimes side by side?

Four tiles come first: New Regime Tax, Old Regime Tax, Lower Tax Option and Annual Difference. Below them is the Old vs New Regime Statutory Computation Ledger, a table with one column per regime. It runs from gross salary down to total tax in the order the law applies, so you can find the step where the two columns part ways. Lines that a regime does not allow read "Not permitted" rather than a misleading Rs 0.

The verdict is a statement about your numbers, not a recommendation. If a regime cannot be computed (for example total income above Rs 2 crore in that regime), only that regime is refused and the other one is still shown.

What does the capital gains table show?

The Capital Gains Schedule and Grandfathering Details table has one row per lot: asset type, buy date, sell date, holding term, cost used, sale value and net gain or loss. Under it is the set-off and carry-forward schedule: current-year short-term and long-term totals, brought-forward losses used, the final taxable short-term and long-term gains, and any loss carried forward.

Two more examples, both with Rs 15,00,000 gross and Rs 6,00,000 basic:

• A long-term sale. Bought 2024-01-10, sold 2026-11-10, cost Rs 2,00,000, sale value Rs 5,00,000, STT on both. The row reads Long-Term with a gain of Rs 3,00,000. All of it counts as long-term gain in total income. The tax is 12.5% on the part above Rs 1,25,000, which is Rs 21,875, plus 4% cess. Tax Twin shows New Rs 1,20,250 and Old Rs 2,80,150.
• A pre-2018 purchase. Bought 2017-06-01, sold 2026-11-05, cost Rs 1,00,000, sale value Rs 4,00,000, 31-Jan-2018 value Rs 2,50,000. The cost used is Rs 2,50,000, so the gain is Rs 1,50,000 and the tax is 12.5% of Rs 25,000 plus cess. Tax Twin shows New Rs 1,00,750 and Old Rs 2,60,650. Leave the 31-Jan-2018 value empty and the page asks for it. Put 0 and it rejects the value.

Loss rules are applied in the schedule and shown line by line. A long-term loss is never set off against a short-term gain, and no capital loss is set off against salary, interest or dividend.

What are the year-end moves?

The Year-End Moves Before 31 March section ranks moves by rupee saving. Each move changes a copy of your profile and re-runs the same calculation. There is no separate formula, so the before and after figures are the same engine at work.

• Top up Section 123 investments to Rs 1,50,000 and own NPS up to Rs 50,000. Old regime only. In the Rs 15 lakh example with one short-term sale, the first moves Old tax from Rs 2,78,200 to Rs 2,31,400, a saving of Rs 46,800. The second moves it to Rs 2,62,600, a saving of Rs 15,600. Notice that Rs 2,31,400 is still above the New regime tax of Rs 1,18,300. A saving inside the Old regime is not a saving against the New one.
• Hold past 12 months. Appears for a lot you ticked as a planned sale if the first long-term date still falls inside the tax year (on or before 31 March 2027). Example: Rs 18,00,000 gross, Rs 7,20,000 basic, a share bought 2026-01-10 and planned for sale on 2026-12-10, cost Rs 1,00,000, sale Rs 4,00,000, STT on purchase Yes. New regime tax is Rs 2,13,200. Selling on 2027-01-11 instead gives Rs 1,73,550, a saving of Rs 39,650. The page prints the assumption "Same sale price on the later date." If STT on purchase is not Yes, the longer hold cannot be computed and the move is not shown.
• Move M3, book an unrealised loss. Add a loss lot under the moves: asset type, purchase date, planned sale date before 31 March, purchase cost and expected sale value. It appears as a move only when you already have capital gains this year for the loss to absorb; otherwise the page says so beside the lot. Example: Rs 18,00,000 gross, Rs 7,20,000 basic, one share sold on 2026-11-10 for Rs 4,00,000 against a cost of Rs 1,00,000, and a loss lot bought on 2026-04-10 for Rs 4,00,000 and sold on 2027-02-10 for Rs 2,00,000. New regime tax moves from Rs 2,13,200 to Rs 1,71,600, a saving of Rs 41,600. The page assumes securities transaction tax is paid on purchase and sale and ignores brokerage.
• Move M5, LTCG exemption harvesting. Type the unrealised long-term gain you could book before 31 March. The page shows your long-term gain so far, the unused part of the Rs 1,25,000 limit, the harvest it considered and a future tax saving at 12.5% plus cess. With Rs 18,00,000 gross, Rs 7,20,000 basic and Rs 75,000 of long-term gain already, typing Rs 2,00,000 gives headroom of Rs 50,000, a harvest of Rs 50,000 and a future saving of Rs 6,500, with Rs 0 change in tax this year. That saving is for a later year, not this one. If booking the gain would raise this year's tax (for instance by pushing income past the rebate limit), a caution box says so before the saving. Selling and re-buying costs are not modelled.

If a move was checked and does not help, the page says how many were left out. These moves are scenarios on your numbers, not advice.

What does Chartered Accountant Review Items mean?

Where the law can be read in more than one way, Tax Twin uses one reading and works out the other too. The Chartered Accountant Review Items box appears only if the other reading would change your final tax after rounding. It names the item, for example the New regime marginal relief reading or the order in which capital gains are placed when surcharge relief is worked out, and cites it. Most profiles show no such box. If yours does, take that line to your own Chartered Accountant.

How do I save a plan and get the PDF?

• Save Plan stores the current numbers in your browser's localStorage, so they stay on that browser and device. Saved Plans lists them. Use Export File to download a copy and Import File to load it on another device. Clearing site data removes saved plans, so export first. Reset returns every input to its default.
• Statutory Calculation Trace. Open it with Inspect to see every step with its section cited.
• Download PDF Pack appears once there is a result. Add an optional plan name first. The PDF is built from the same figures as the page: result, profile, regime comparison, capital gains schedule, moves, review items, trace and limits.

What does Tax Twin not do?

• It covers a resident individual below 60 only, and total income up to Rs 2 crore in each regime.
• It refuses business, trading, F&O, house property and any asset other than listed shares and equity mutual fund units.
• It does not match lots for you.
• It does not compute TDS, advance tax, interest or late fees.
• Brought-forward losses and other Chapter VIII deductions are your numbers and are not validated.
• Perquisites, ESOP and arrears are not covered.
• It is an estimate for planning, not tax advice. Not reviewed by a Chartered Accountant. The answer is only as good as the numbers you type. If a number looks wrong, use the "Report something wrong" button on the tool page.

Last reviewed: October 2026, for tax year 2026-27. For other tools, see the HeyArtha guides and the calculators hub. Long-term gains on property follow different rules, covered in Property Capital Gains: Indexation vs 12.5%.

Next in series: In-Hand Salary Calculator India: Every Field and Result.

Regulatory & Educational Disclaimer: The content on HeyArtha is published strictly for educational, career awareness, and personal reflection purposes. Nothing contained in this article constitutes financial, investment, legal, or taxation advice. We are not a SEBI-registered investment advisor or research analyst. Trading and investments in financial markets involve risk of capital loss. Always consult a certified professional before making financial commitments.