Many taxpayers often find themselves confused when choosing between the new tax regime and the old regime. The dilemma becomes more serious when someone files their Income Tax Return (ITR) under one regime, only to later realize that the other regime would have reduced their tax liability significantly—or even brought it down to zero.

This exact situation recently surfaced when a taxpayer discovered that filing under the old regime would have meant zero tax liability, but they had already filed under the new regime. The big question is: Can you revise your return and switch the regime after filing?

To clarify this, Moneycontrol spoke with tax expert Balwant Jain, who explained the current rules in detail.

New Tax Regime is Now the Default

Jain pointed out that under the Income Tax Act, the new regime is the default option. This means that if a taxpayer wants to use the new regime, they don’t need to make any special selection. However, if someone wants to file under the old regime, they must actively choose it while filing the return.

For individuals with business income, there is an additional requirement: they must file Form 10IEA before the ITR filing deadline if they wish to opt out of the new regime. Once a taxpayer with business income chooses the old regime, they are required to continue with it until their business income ceases. Importantly, such taxpayers are allowed to switch regimes only once in their lifetime.

For Salaried and Non-Business Taxpayers

If you do not have any business income, the rules are much simpler. Salaried or non-business taxpayers can select the old tax regime directly while filing their ITR, without the need to submit any separate form.

However, this choice must be made before the ITR filing deadline. If you miss the deadline, you cannot change the regime in your original or revised return.

For the current financial year 2024-25, the last date for filing ITR has been extended to September 15, 2025.

Can You Revise Your Return to Switch Regime?

According to Jain, taxpayers are allowed to file a revised return as many times as needed until December 31, 2025, for FY 2024-25.

This means that if you initially filed your return under the new regime, you can revise it and select the old regime, provided:

• 
  

  You do not have business income (or have already filed Form 10IEA if you do).

  
  


• 
  

  You revise your return before the December 31 deadline.

  
  

In other words, yes, you can switch from the new regime to the old regime by filing a revised return, but the option is time-bound and subject to your income type.

Expert Advice: Compare Both Regimes First

Tax experts strongly recommend that before filing ITR, taxpayers should always compare their tax liability under both regimes. The old regime continues to offer multiple deductions and exemptions such as 80C, 80D, HRA, LTA, and home loan interest, which can significantly lower tax liability.

On the other hand, the new regime offers lower tax rates but with limited deductions. This makes it beneficial for those with fewer investments or deductions.

Failing to make this comparison often leads to regret after filing, especially when the old regime could have reduced the tax outgo or eliminated it entirely.

Key Takeaways for Taxpayers

1. 
   

   New regime is the default – no selection required.

   
   


2. 
   

   Old regime must be selected while filing, and business taxpayers must file Form 10IEA.

   
   


3. 
   

   Non-business taxpayers can switch to the old regime while filing without any form.

   
   


4. 
   

   ITR filing deadline for FY 2024-25 is September 15, 2025.

   
   


5. 
   

   Revised returns can be filed multiple times until December 31, 2025.

   
   


6. 
   

   Business taxpayers can switch regimes only once.

   
   

Bottom Line

If you have already filed your ITR under the new tax regime but later find that the old regime saves you more tax, you still have a chance to switch—by filing a revised return before December 31, 2025.

However, taxpayers with business income need to be more careful, as their flexibility is limited and requires Form 10IEA.

The best strategy is to always calculate tax liability under both regimes beforehand and then make an informed decision. Doing so can help avoid unnecessary complications and ensure maximum savings.