from google play store
If you are a prepaid Airtel user then you will be able to get absolutely free 2GB or 4GB or 6GB according to your plan. Of course, recharge your prepaid number from third-party apps or offline anywhere, but if you recharge through the Airtel Thanks app then you will be eligible for free data voucher according to plan. Free data vouchers are shown along with the plan and this data will be used after daily data is exhausted.
To get a free data voucher with recharge you must recharge from the Airtel Thanks app. Download the Airtel Thanks app from the Google play store and sign in via your prepaid Airtel number. Click on the recharge option, check your plan and recharge your number from the Thanks app using Airtel money or another payment mode. After successful recharge, you will get a free data voucher according to your plan. Also, you get a cashback of rupees 20 or 40 according to your pack, but you have to open the Airtel Savings accounts on this number.
2GB free data voucher on recharge plan amount:─ 219, 249, 298, 349, 398
4GB free data voucher on recharge plan amount:─ 399, 449, 558, 699
6GB free data voucher on recharge plan amount:─ 598, 698
image from Airtel Thanks