The T-Mobile logo at MWC 2018.

Google Fi — which started out as Project Fi — is an online-only wireless carrier. The big selling point of Google Fi is that you only pay for the data you use, and that the data amount can fluctuate from month-to-month. Like other services from Google, it offers a different approach to an established paradigm — in this case, wireless service.

On the other hand, T-Mobile‘s service is a little more generic. There are physical shops you can visit and you pay a flat fee for unlimited data, which might result in you paying more money than you need for data you’re not using.

Depending on your situation, the Google Fi vs T-Mobile question might be easy to answer. However, if you don’t know much about either service or are currently a subscriber to one with little knowledge of the other, we’re here to help you settle the Google Fi vs T-Mobile debate once and for all!

Let’s talk about each aspect of the two services and see which one works better for you.

Google Fi vs T-Mobile: Talk and text

Gboard on the Pixel 2XL.

As with most carriers these days, both T-Mobile and Google Fi offer unlimited talk and text when you are in the United States calling or texting someone who also lives in the United States. This unlimited voice/text package is incorporated into nearly every T-Mobile plan and is part of the $20 base fee for Google Fi.

T-Mobile also offers unlimited free calls and texts to and from Canada and Mexico, while Google Fi only offers free texting to countries outside of the United States. Calls to and from both Canada and Mexico will be subject to a $0.20-per-minute rate on Google Fi.

There will be more info on international Google Fi and T-Mobile services a bit further down!

Google Fi vs T-Mobile: Data

Google Fi vs T-mobile data plans comparison

Our smartphone usage gets more and more data-heavy with every passing year, so how much data you are allowed to use on your wireless plan is of the utmost importance!

T-Mobile keeps things relatively simple: for a flat fee every month, you can use as much 4G LTE data as you wish. That flat fee varies depending on which plan you decide to go with. The basic plan — T-Mobile Magenta — costs $75 per month, with all taxes and fees included in that price. There are more expensive plans (like T-Mobile Magenta Plus) and a few cheaper ones, too (such as T-Mobile Essentials). However, no matter which plan you choose your data will be unlimited.

Google Fi takes an “a la carte” approach to mobile service, charging you $10 for every gigabyte of data you use, and prorating that charge by $1 increments. For example, if you use 1.9GB of data in a month, you’ll be charged $19 for that data.

If you’re a heavy data user, Google has you somewhat covered: with Google Fi, charges are capped at 6GB of monthly data for people with just one line. For example, if you use 7.6GB of data one month, you will be charged $60 — not $76 — because $60 is as high as the charges can go.

However, this data grace period has a limit itself: if you go over 15GB in one month with one line, you’ll either be throttled (see next section for more on throttling) or will have to start paying $10 per GB again. In other words, you pay per GB from 0-6GB of data, don’t pay from 6-15GB of data, and then start paying again after 15GB (or choose to be throttled).

As we use more and more data, we need a plan that can accommodate that consumption. But we also don't want to pay more than we must.

Remember though that data charges with Google Fi are on top of the $20 base level fee for talk and text. With that factored in, the most you’ll pay for talk, text, and data on Google Fi is $80, assuming you don’t have any additional international charges and choose to be throttled after 15GB of use. Google Fi also will charge taxes and fees on top of this $80.

The essential takeaway here is that if you use a lot of data, T-Mobile offers you all the data you could want at a flat rate of $75 per month, taxes and fees included. Google Fi, however, will charge $80 for unlimited data with additional taxes and fees, clearly making T-Mobile the better option when it comes to using lots of data.

If you are not a big data user, then Google Fi is likely the better option, as you’ll only pay for the data you use. For example, if you use less than 2GB of data in any given month, your Google Fi bill could be half of what you’d pay with T-Mobile.

Google Fi vs T-Mobile: Throttling

Samsung Galaxy S6 Internet data Speedtest

There’s more to the story here when it comes to so-called “unlimited” data. Both T-Mobile and Google Fi will throttle your data service if you use more than what each company considers an appropriate amount. “Throttling” means your service is still active — i.e., you can still access the internet using your mobile data — but your experience will be quite slow.

With T-Mobile, your service might get throttled after 50GB of use in one month, while Google Fi could start throttling you after only 15GB of use.

However, as mentioned above, with Google Fi, you can choose not to be throttled and instead just continue paying $10 per GB of data. This gives you, theoretically, all the high-speed data you could ever want without fear of throttling, assuming you’re OK paying $10 for every GB after 15GB. Be careful though: if you used 50GB of unthrottled data on Google Fi, your monthly bill would be a whopping $430!

This shows once again that if you are a heavy data user, T-Mobile is the better option. If you often find yourself going over 15GB of data per month, you’re going to have a bad time on Google Fi.

Google Fi vs T-Mobile: Service

A map of T-Mobile coverage in North America as of February 2019.


Believe it or not, Google Fi’s primary network is exactly the same as T-Mobile’s. That’s because Google Fi is a mobile virtual network operator (MVNO), meaning that it doesn’t own its own network towers or spectrum. Instead, it buys network access from T-Mobile and then sells that to consumers for a profit.

In other words, a coverage map of T-Mobile’s network and a coverage map of Google Fi’s will look the same.

However, there is one crucial difference when it comes to Google Fi, which is that it also buys wireless spectrum from other carriers, including Sprint. This means that if you are in an area where T-Mobile service is spotty, but Sprint service is good, Google Fi will connect you to a Sprint tower instead at no additional charge — and without you even knowing. This is something T-Mobile does not offer.

Unless you use a Google Fi-certified device, Google Fi's service map is exactly the same as T-Mobile's.

Unfortunately, this ability to switch back and forth from one network to another is not compatible with all Android phones. Instead, this feature is only available to “phones designed for Fi,” and that list is quite small.

To be clear, if you do not own a phone designed for Google Fi, you will only have access to T-Mobile towers, making Google Fi and T-Mobile network service exactly the same.

Consult the next section for more on devices.

Google Fi vs T-Mobile: Devices

Backside photo of the Google Pixel 3 next toa Samsung Galaxy S10 on a wooden surface.

64-bit support is standard in today’s mobile devices, so this move just makes sense.

T-Mobile is a GSM network. You can read more about what that means here, but the general gist is that its service is based on a globally-recognized technology. As such, you can buy a phone from pretty much any source and it will likely work on T-Mobile.

The only thing you’ll need to keep in mind is that some international phones won’t be able to access 4G LTE speeds on T-Mobile’s network. However, this isn’t something you have to worry about if you’re buying your device in the United States.

If you don’t want to bring your own device to T-Mobile, you can visit a T-Mobile store and buy a phone directly from the carrier. You can also buy phones online from

Google Fi is more complicated. As mentioned in the previous section, to take full advantage of Google Fi’s network-switching capabilities, you’ll need to own or buy a phone designed for Fi. As of today, the entire list of “designed for Fi” phones is here:

If your device is not on that list, you won’t have the ability to switch between networks on Google Fi. You will be using T-Mobile towers exclusively, almost as if you were a T-Mobile customer.

If you don’t want to use one of those phones, you can consult this list to see the full range of devices that work on Google Fi. There are phones from Samsung, Huawei, HTC, OnePlus, and even Apple on the list. However, they won’t be designed for Fi and won’t get to seamlessly switch networks.

Google Fi vs T-Mobile: Group/family plans

Backside of three different Motorola android phones

Both T-Mobile and Google Fi encourage you to add more lines to your account to take advantage of discounts. The more accounts you add, the more you can potentially save.

For the T-Mobile Magenta plan, your first line is $75. Your second line is $55, and your third, fourth, fifth, sixth, seventh, and eighth line will be $25 each. For a family of four, you’d pay $180 per month, or $45 per line if you split it evenly.

Keep in mind those prices reflect paying your bill manually rather than using autopay. If you use autopay, your bill is lower (see Billing section below).

As with a single-line T-Mobile plan, a family plan gets unlimited text, talk, and 4G LTE data. It should be noted that data throttling doesn’t begin if your collective data usage goes above 50GB, it starts when each individual line goes over 50GB.

With Google Fi family plans, the company sticks with its a la carte approach to data. Each line you add is an additional $15 on top of the $20 base, and then your data charges amount to $10 for every GB of usage.

However, the limit for how much data you can use before billing caps out goes up with each new line. For one line, this is 6GB (as described in the Data section above). For two lines, that limit goes up to 10GB and up to 12GB for three lines, and so on. In other words, how much data your family uses on Google Fi makes a huge difference for your bill.

Once again, if your family uses a lot of data, Google Fi will likely be much more expensive than T-Mobile.

For example, if your family of four uses a collective 20GB of data every month on T-Mobile, your monthly bill will be $180 (without autopay). If that same family uses 20GB collectively on Google Fi, the monthly bill will be $205 plus taxes and fees ($20 base + $45 for three additional lines + $140 for over 14GB of data). If your family of four uses 10GB collectively over one month, your Google Fi bill will be $165 — less than T-Mobile. However, that Google Fi price doesn’t include taxes and fees and using autopay on T-Mobile will make your bill much cheaper.

The ultimate takeaway here is, once again, that Google Fi’s service becomes more expensive than T-Mobile if you use a lot of data. Only frugal data users will see a financial benefit to Google Fi.

Google Fi vs T-Mobile: International service

Showing video of the eiffel tower on a black Samsung Galaxy

International service on a United States carrier used to be a nightmare. Nowadays though, things are a lot more straightforward and service is a lot cheaper.

On the T-Mobile Magenta plan, you can use wireless data and send text messages as much as you like at no additional charge in over 200 countries. However, that data will be very slow, capped at 128Kbps. At that speed, it would take about six minutes to download one 5MB file, such as an MP3 or a large PDF.

It should be noted though that you get 5GB of high-speed data per month in Canada and Mexico. After you use 5GB in one month in one of those countries, your speed gets knocked down to the usual 128Kbps limit.

The T-Mobile Magenta Plus plan doubles that international speed limit to 256Kbps, which is better but still much slower than the speeds you’ll likely be used to in the U.S.

Google Fi offers the same free international texting as T-Mobile but handles international data roaming a bit differently. Instead of capping your use at any one speed, your data speed varies depending on where you are. For example, your speeds in a place like London might be just as fast as the LTE speeds you enjoy at home, while the speed on a small island like Corsica might be more in line with the 128Kbps speeds T-Mobile Magenta subscribers will see.

Frequent international travelers will likely love Google Fi's speeds when in faraway countries.

Regardless of speed, international data costs the same as domestic data on Google Fi: $10 per gigabyte.

If you are using a non-Fi device (see the Devices section above), you may or may not see the same speeds internationally as a Fi-certified device. It varies.

As for phone calls, both T-Mobile and Google Fi will charge you for calling either to or from international destinations. The rates can vary, but $0.20 per minute is the average charge. As mentioned before, T-Mobile will not charge you for calls to or from Canada and Mexico, while Google Fi will.

Google Fi vs T-Mobile: Additional perks

T-Mobile LiveNation partnership

Both T-Mobile and Google Fi offer perks in addition to your regular service.

All T-Mobile Magenta customers get access to T-Mobile Tuesdays, an app that gives you free and discounted stuff every Tuesday (naturally). The free stuff can vary from incredibly cool (like a free subscription to Pandora Plus for a year or a free taco from Taco Bell every week) to incredibly lame (a free drink with purchase of a full meal at a restaurant, for example). The app also offers discounts on devices, free T-Mobile swag, and the ability to enter giveaway contests.

Additionally, any group T-Mobile plan with two lines or more gets access to free Netflix (a Basic plan for Magenta and a Standard plan for Magenta Plus). T-Mobile calls this Netflix On Us, and it effectively subsidizes your Netflix subscription. The base Netflix plan is free, and higher-end Netflix plans get discounted. You can read more about how it works here.

T-Mobile plans also include hotspot data, in which you use your phone as an internet hub for your laptop or tablet. Magenta customers get 3GB of high-speed hotspot data per month with unlimited 3G speeds after that. Magenta Plus customers get 20GB of high-speed hotspot data.

Both T-Mobile Magenta plans also offer free in-flight data and texting if your flight supports Gogo.

Google Fi has a few perks as well. The biggest is that, if you’re using a phone designed for Fi, your service will not only automatically switch between carriers but also automatically switch to millions of secure Wi-Fi hotspots. This helps save you data, as your Wi-Fi use doesn’t count towards your data charges.

You also get access to a Google Fi VPN service that secures all communication: voice, text, messages, etc. You also can use RCS messaging with other devices on Fi (although RCS won’t be locked to Fi for much longer). Once again, though, these perks only work with Google Fi-certified devices.

Google Fi also offers free data-only SIM cards to use your data on additional devices. This is helpful if you want the benefits of Google Fi but don’t want to switch your phones. You could, theoretically, buy a Motorola Moto X4 (one of the cheapest Google Fi-certified devices) and make it into a mobile hotspot using the data-only SIM card. Connect your main phone to the Moto X4 and you’ll essentially have the benefit of Google Fi network switching on your phone that isn’t Fi-certified.

Both Google Fi and T-Mobile offer 24/7 customer support, connecting you with a human quickly.

Google Fi vs T-Mobile: Billing

Photo of a wallet with notes and credit cards sticking out.

T-Mobile offers many different ways to pay your bill. You can sign up for autopay which automatically withdraws cash from your connected bank account or credit card on the bill date. If you use this service, T-Mobile cuts down the price of your wireless service by $5 for each line. For example, the $75 T-Mobile Magenta plan goes down to $70 for one account if you use autopay. A family of four would pay $180 each month without autopay, but only pay $160 per month with it.

If for some reason you don’t want to save money using autopay, you can agree to pay your bill manually. You can do this online, over the phone, or even walk into a T-Mobile store and pay there.

Google Fi only offers one option: autopay. You cannot pay your bill manually online or over the phone. The only time a manual charge would be possible is if there were something wrong with your automatic payment and you had to rectify that situation with a manual charge. There is no discount for using autopay since it’s the only option.

Final verdict: Google Fi vs T-Mobile

Google Fi ad for different kind of phone plan.

Google Fi

Ultimately, T-Mobile will be the better service for the majority of users, especially if you are signing up for a family plan or use a lot of data.

Users who fall into some specific categories, however, will find Google Fi can save them a ton of cash in the long run. These users do not have a family plan, own or are willing to buy a Google Fi-certified device, and are willing to curb their data usage as much as possible to keep their bill low.

Additionally, users who do a lot of international travel might find Google Fi to be better for them due to better data speeds, although T-Mobile’s offerings in Canada and Mexico stand out.

Check out the table below for a quick synopsis of our Google Fi vs T-Mobile comparison:

 T-Mobile Magenta (with autopay)Google Fi
Talk and Text$70 for first line
$50 for second line
$20 each for lines 3-8
$20 for first line
$15 for each additional line
DataUnlimited 4G LTE$10 per GB of 4G LTE
No extra charge if you go over 6GB
ThrottlingOver 50GB in one monthOver 15GB in one month
Choice to pay more instead of throttle after 15GB
ServiceT-Mobile network onlyT-Mobile network only
(Additional networks with certain devices)
DevicesMost domestic GSM devicesMost domestic GSM devices
Small list of Fi-certified devices enhance experience
Family Plans2 lines, 50GB/each -- $120
3 lines, 50GB/each -- $140
4 lines, 50GB/each -- $160
(Based on 50GB throttle limit)
2 lines, 3GB/each -- $95
2 lines, 15GB total -- $135
3 lines, 3GB/each -- $140
3 lines, 15GB total -- $170
4 lines, 3GB/each -- $185
4 lines, 15GB total -- $205
International200+ countries
Free texting everywhere
Free calls to/from Canada and Mexico
Average of $0.20/min. for other calls
5GB of high-speed data in Canada and Mexico
Data speeds elsewhere capped at 128KBps
All data free with plan
200+ countries
Free texting everywhere
Average of $0.20/min. for all calls outside US
Data speeds vary by location
Data costs same as domestic ($10/GB)
PerksT-Mobile Tuesdays
Netflix On Us
Free Gogo in-flight data/text
3GB of high-speed hotspot, unlimited 3G after
24/7 customer support
Access to free Wi-Fi, RCS, and VPN (with certified devices only)
Free additional data-only SIM
Hotspot at 4G LTE speeds ($10/GB)
24/7 customer support
Manual pay online, over phone, in-store
Autopay only
Taxes & FeesIncluded in pricesNot included in prices

Where do you fall on the Google Fi vs T-Mobile debate? Do you currently subscribe to either service? Are you going to stay or does this article make you think you should switch? Let us know in the comments!

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