Source: Android Central
Best answer: Yes, you may upgrade your existing Mint Mobile to the Unlimited plan by paying the difference in price. All you need to do is log into your account.
- 35GB of high-speed data with a 5GB hotspot: Mint Mobile Unlimited (From $30/mo. at Mint Mobile)
Upgrade to a fresh new plan mid-cycle on Mint Mobile
Mint Mobile originally came with three data sizes and three plan lengths, which would work for most people. While 12GB is fine for the majority of smartphone users, especially if they make good use of Wi-Fi networks, some people just need more.
Luckily Mint Mobile now has an unlimited plan that comes with 35GB of high-speed data. This plan helps Mint Mobile to become one of the best MVNOs with unlimited data.
If you're using any one of Mint Mobile's three smaller data plans, you can upgrade to any larger plan mid-cycle by paying the difference in price. Note that you cannot downgrade your plan until the end of your current term.
There are a couple of things to keep in mind if you are considering the upgrade. The first thing is that videos will only stream at 480p quality on the unlimited plan. The next thing is that hotspot data is limited to 5GB. If you use more than 5GB of your data on other devices via tethering, you may be limited with this new plan. Still, for the vast majority of people, 5GB of hotspot data will be more than enough.
You also cannot add additional data to your unlimited plan in the same way you could with the smaller plans. If you need more than 35GB of data, Mint Mobile isn't going to be a feasible solution even if you're willing to pay for it.
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