Check your Viettel plan: from My Viettel to Viettel Tammi

Which app has replaced My Viettel?

Viettel’s announcement dated 17/09/2026 explains the transition of My Viettel services to Viettel Tammi from 01/10/2026. When following an older My Viettel guide, start with the current app through viettel.vn/tammi/app.

tammi.cloud is an independent information website, not the Viettel Tammi app. We do not collect your account details, subscriber number or OTP.

Sign in and check three plan details

Open Viettel Tammi and sign in with your Viettel number using the official instructions. Select the correct subscription if your account manages several numbers or connections. Find the subscription or current-plan information to check data and expiry; do not assume buttons remain in the positions shown in old My Viettel screenshots.

1. Note the name of your active plan.
2. Check the remaining data and expiry time shown in the app.
3. Check whether data is allocated daily or for the whole cycle; the advertised total is not necessarily available to use in full today.

Check renewal terms before changing or cancelling

Open the plan details and read the next-cycle price and renewal conditions. For example, the SD120 page states that renewal follows the prepaid cycle or the end of the postpaid month; check other plans individually instead of assuming the same rules apply.

Viettel’s product information distinguishes cancelling renewal from cancelling the plan. Read the confirmation to understand how long access continues, which benefits stop and whether another confirmation is required. Do not assume that selecting “Hủy” (Cancel) always preserves your data until the end of the cycle.

When the app does not show enough information

Viettel’s documentation describes checking allowances by texting KTTK to 191. On a dual-SIM phone, check the response for the correct SIM. If you want to change plans but cannot confirm eligibility, contact Viettel support instead of repeatedly sending registration commands.

Before finishing, save the plan name, expiry date and completion message. Turn off mobile data if you do not know the out-of-plan rate after cancellation; turn it back on once you have confirmed how you will continue using the service.