Hra exemption

Hi,

One of my frnd gets HRA, But since he couldnt submit the rental slips to the HR in his company he was denied HRA Examption and was issued form 16.

Now he has all the rental slips. I want to know whether he can claim that exemption of HRA and cliam the TDS refund. or the income tax dept will only go by the form 16 issued.

Kindly advice