Currently most mobile operators provide unlimited calling plans within India. While some of them are not available while in Roaming, some are available while Roaming. Here, we will discuss the started plans (as of now) that are available in Roaming too. Jio anyway has the same tariff in roaming as well as in home state.

Jio

349 plan has 10 GB data for a month.

Currently there is a promotion to get the benefit 10 + 10 GB for two months.

When you recharge a voucher when existing plan is active, Jio will queue it and make it available once your existing plan gets over. For example, if I recharge for 303 and 503 together in Jio, it gets queues up and can use one after the other/

However, other providers will kill your current plan and activate the new plan effective the date of recharge. This means part of your old plan is lost. Other providers provide good offers mostly before the expiry of your current offer to get benefited from this lose.