If you changed jobs during FY 2025-26, you will receive two Form 16s — one from each employer — and there is a real chance that, added together, they leave you with a tax bill you were not expecting. The reason is simple and almost always the same: each employer calculated your tax as if their salary were the only income you had that year. Both gave you the standard deduction, both gave you the section 87A rebate, both applied the lower slabs from scratch. Individually the maths was right. Combined, far too little TDS was deducted.
The good news is that this is entirely fixable at filing time, and if you plan for it you will not be caught out. The bad news is that people who simply “upload both Form 16s and file” without reconciling often end up with a demand plus interest under sections 234B and 234C. Here is exactly why the gap arises, a worked example that shows how large it can get, and the correct way to merge two Form 16s into one clean return.
Why two Form 16s create a shortfall
Your employer deducts TDS on salary by estimating your tax for the full year on the salary they pay you. A new employer has no visibility of what you earned before you joined — unless you tell them. So each employer independently:
Grants you the standard deduction (Rs. 75,000 in the new regime, Rs. 50,000 in the old). Applies the basic exemption and the lowest slabs from zero. Applies the section 87A rebate if the income they see is within the limit. And, in the old regime, may give you the full section 80C / 80D deductions again.
Each of these is a once-a-year benefit. When two employers each grant them, you have effectively claimed them twice — and your total TDS falls far short of your real liability. That shortfall lands on you at filing time. You can estimate your combined position quickly with our Multiple Form 16 Tax Calculator.
Worked example: how the 87A rebate trap wipes out your TDS
Priya switched employers in the middle of FY 2025-26 and chose the new regime. Company A paid her Rs. 7,50,000 for April to September; Company B paid her Rs. 6,00,000 for October to March. Total salary: Rs. 13,50,000.
See what each employer did on its own:
| Computation | Company A | Company B |
|---|---|---|
| Salary paid | Rs. 7,50,000 | Rs. 6,00,000 |
| Less: standard deduction | Rs. 75,000 | Rs. 75,000 |
| Taxable salary (as each employer saw it) | Rs. 6,75,000 | Rs. 5,25,000 |
| Tax before rebate | Rs. 13,750 | Rs. 6,250 |
| Less: section 87A rebate (income below Rs. 12 lakh) | (Rs. 13,750) | (Rs. 6,250) |
| TDS actually deducted | Nil | Nil |
Both employers deducted zero TDS, because each saw an income below Rs. 12 lakh and applied the rebate. Now look at Priya’s real position when the two salaries are combined:
| Correct computation (combined) | Amount (Rs.) |
|---|---|
| Total salary (7,50,000 + 6,00,000) | 13,50,000 |
| Less: standard deduction (once only) | 75,000 |
| Taxable income | 12,75,000 |
| Tax: 5% of 4L + 10% of 4L + 15% of 75,000 | 71,250 |
| Section 87A rebate (income now above Rs. 12 lakh) | Not available |
| Add: health & education cess at 4% | 2,850 |
| Total tax payable | 74,100 |
Priya’s actual liability is about Rs. 74,100, against which nil TDS was deducted. Two things caused it: the standard deduction was granted twice, and — the bigger hit — because her combined taxable income crossed Rs. 12 lakh, the section 87A rebate that both employers assumed disappears entirely. On top of the demand she will pay interest under sections 234B and 234C for not having paid this as advance tax through the year. You can quantify that interest with our 234A/234B/234C Interest Calculator.
The prevention: Form 12B, given to your new employer
The cleanest fix happens before filing. When you join a new employer mid-year, give them Form 12B — a declaration of the salary you earned and the TDS deducted at your previous job. Armed with this, your new employer computes TDS on your combined income for the year, grants each benefit only once, and deducts the correct amount month by month. No shortfall, no interest, no year-end surprise. (For transitions on or after 1 April 2026, employers are moving to the equivalent declaration under the new Income-tax Act, 2025 — the principle is identical: disclose your previous salary.)
If you did not submit Form 12B — most people don’t — you can still fix everything at the return stage, and often it is wise to pay the shortfall as advance tax before 15 March to limit 234B/234C interest.
How to merge two Form 16s correctly at filing
The principle is that you file one return combining both jobs, and each once-a-year benefit is claimed once. Step by step:
1. Add up the salary from both Form 16s
Take the gross salary from Part B of each Form 16 and add them. This combined figure is your salary income — not the higher of the two, and not each treated separately.
2. Apply the standard deduction only once
Rs. 75,000 (new regime) or Rs. 50,000 (old regime) is deducted once from the combined salary, no matter how many employers you had.
3. Claim exemptions and Chapter VI-A deductions once
HRA is worked out for the actual rent-paying periods, but exemptions like this, and old-regime deductions under 80C, 80D and 80G, are each subject to their own single annual ceiling — never the sum of what two employers allowed.
4. Add up the TDS from both
Total the TDS from Part A of both Form 16s, and — this is essential — cross-check it against your Form 26AS and AIS on the income-tax portal. Only TDS actually reflected there can be claimed as credit.
5. Compute the real tax and pay the balance
Apply the slab rates to your combined taxable income, subtract the total TDS credit, and pay whatever remains as self-assessment tax before you file. Running the numbers through our Income Tax Calculator first tells you the shortfall so there are no surprises.
Old regime vs new regime: pick one, apply it to the whole year
You cannot mix regimes across your two jobs. Even if one employer deducted TDS under the old regime and the other under the new, at filing you choose a single regime for the whole year and recompute. Often the shortfall itself changes which regime is cheaper, so compare both before locking in. Remember that in the old regime the double-80C problem is real: if each employer gave you the full Rs. 1.5 lakh 80C benefit, your combined return can only claim Rs. 1.5 lakh in total.
Key takeaways
- Two employers each compute TDS on their salary alone, so both grant the standard deduction, the basic exemption and the 87A rebate — leaving your combined TDS short and creating a demand.
- The sharpest trap in the new regime: two salaries that are each below Rs. 12 lakh can combine to cross Rs. 12 lakh, at which point the section 87A rebate vanishes entirely and tax appears where both employers deducted nil.
- The standard deduction (Rs. 75,000 new / Rs. 50,000 old) and all Chapter VI-A deductions can be claimed only once in your return, not once per employer.
- Prevent it by giving Form 12B to your new employer when you join; fix it at filing by combining both Form 16s, verifying TDS against Form 26AS/AIS, and paying the balance before filing.
- Unpaid tax carried to filing attracts interest under sections 234B and 234C — paying the shortfall as advance tax before 15 March reduces it.
Frequently Asked Questions
Do I file two returns if I have two Form 16s?
No. You file a single ITR that combines the salary and TDS from both employers. Two Form 16s, one return.
Can I claim the standard deduction twice because I have two Form 16s?
No. The standard deduction is a once-a-year benefit — Rs. 75,000 in the new regime or Rs. 50,000 in the old — and is allowed only once on your combined salary, even though each employer may have granted it separately.
Why do I owe tax when both employers already deducted TDS?
Because each deducted TDS as if their salary were your only income, applying the lower slabs, standard deduction and 87A rebate independently. When the salaries are combined your income falls in a higher slab — and may lose the rebate — so the total TDS is less than your real liability.
How do I avoid this next time I switch jobs?
Give your new employer Form 12B (or the equivalent declaration under the new Income-tax Act, 2025 for changes from 1 April 2026) stating your previous salary and TDS. The new employer then deducts on your combined income and there is no shortfall.
Will I have to pay interest on the shortfall?
Usually yes — interest under sections 234B and 234C applies when advance tax falls short. You can limit it by paying the balance as advance tax before 15 March rather than waiting until you file. Estimate it with our interest calculator.