It used to be a foregone conclusion that if you were shopping for wireless service, you’d end up at one of the Big Four wireless carriers. Until about five years ago, prepaid and no-contract service in the United States wasn’t particularly popular, and typically reserved only for those who prioritized spending the least amount of money over all else.
Today, these networks are viable alternatives to the likes of Verizon, T-Mobile, AT&T and Sprint, no matter what phone you own or how much you’ve got to spend. And since 2015, one of the most intriguing options on the market has been Project Fi, Google’s attempt at making wireless service simpler.
A year ago, the service underwent a significant transformation, dropping the “Project” aspect of the name, and rebranding to simply Google Fi. In the same breath, Fi expanded access to include nearly all unlocked phones, after previously restricting service to Pixel devices and select Android handsets from Motorola.
We liked Fi when we first tested it in 2017, but the service has changed considerably in the last two years. In many ways, it’s improved — though there are still a few catches here and there, especially depending on the device you bring to the network.
Updated Dec. 11, 2019: Our Google Fi review has been updated with information concerning new features for unlocked phones on the network, as well as support for 5G devices.
How Google Fi works
Google Fi is an MVNO (mobile network virtual operator), meaning that it uses other networks to deliver service. In Fi’s case, those networks are T-Mobile, Sprint and regional carrier U.S. Cellular. By consolidating all three, Google provides better coverage than any of them individually.
However, not every device on Fi can connect to all three of these networks. Specific phones sold on the Google Fi website, including the Pixel 4 and Pixel 4 XL as well as the Pixel 3a and Moto G7, are optimized to support dynamic switching between the trio of networks. While you now can bring most GSM unlocked handsets to Fi, including iPhones, they won’t be able to switch networks, and will instead be locked to T-Mobile. Fortunately, Google supplies a handy tool to help you determine whether or not your phone will work on the service, as well as a checklist that identifies which of Fi’s features it will support.
If you do have a Fi-optimized device, switching between the networks is seamless, and happens without the user knowing. Google’s software is designed to use the fastest, most reliable signal at any given time, and also automatically connects to over 2 million Wi-Fi hotspots worldwide to save data consumption. In fact, Google says it’s been able to speed up the handoff between between LTE and Wi-Fi as of late, trimming times by up to 40 percent. Best of all, the service works overseas, too, at the same pricing as it does at home in more than 170 countries.
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For a while now, Google has secured its public Wi-Fi hotspots through its own VPN, so that your connections couldn't be intercepted by interlopers. Recently, the company went a step further for Fi subscribers, allowing them to channel mobile network and private Wi-Fi traffic over its VPN as well. This feature is optional, and while it was initially exclusive to Fi-optimized devices, you can now take advantage of it no matter what Android phone you bring to the network. You should note, however, that it consumes roughly 10 percent more data by Google's estimation. That's important, because Fi's individual plans charge you based on the data you use, and VPN traffic adds to your data tally.
Now that T-Mobile has launched its nationwide 600MHz 5G network, those who bring supported 5G phones to Google Fi, like the OnePlus 7T Pro 5G McLaren and Galaxy Note 10 Plus 5G, should be able to use those devices over the Uncarrier's 5G network by putting in a Google Fi SIM.
But just because you can doesn't mean you should, or that it's even easy in the first place. Neither of those devices are sold unlocked, so you'd have to purchase one from T-Mobile with a plan, then immediately pay out the remaining value of your phone and get it unlocked. Even then though, you'd be left with a handset that won't support one of Fi's primary features — auto switching between Sprint, T-Mobile and US Cellular's networks for the best LTE signal.
Theoretically, it'll be much easier to bring a 5G phone to Fi sometime in 2020, once phones with Qualcomm's 5G-capable Snapdragon 865 chipset hit the market. It's also assumed the next Pixel flagship will utilize that processor. If it does, it'll assuredly be sold through Fi, meaning Google will have to provide a lane for owners to use 5G on their network.
How much Google Fi costs
What really makes Google Fi really special is its pricing structure. Plans begin at $20 for the first line, and $15 for every line thereafter. That initial fee essentially covers your talk and texting. You pay an additional $10 per gigabyte for the data that you use, plus taxes and fees, billed at the end of the month. Auto pay is mandatory.
For example, an individual who consumes 3GB will pay a total of $50 at the end of their billing cycle. (That’s $20 for the phone line, plus another $30 for the data.) Google Fi is also unusual in that its rates don’t round up when you go over a certain amount of data. Use 2.1GB of data, and you won’t be charged as if you used 3GB like you might be at most other carriers. Instead, Google charges you $21, as each 100MB of data costs $1.
Because Fi prominently incorporates public Wi-Fi networks, depending on where you live, you may not even need to purchase quite as much data as you would on other carriers. That said, having used Fi extensively in New York City, we’ve found that Google’s hotspots aren’t as ubiquitous as you’d hope.
| Carrier | LTE Data | Monthly Cost | Notes |
| Google Fi | 3GB | $50 | $20 per line fee plus $10 per GB of data; unused data credited to next month’s account. |
| Boost | 3GB | $35 | Unlimited plan costs $50 |
| Metro by T-Mobile | 2GB | $30 | 10GB plan costs $40; Unlimited plans start at $50 |
| Sprint | Unlimited Basic | $60 | Unlimited Plus ($70) and Unlimited Premium ($90) also available, offering more perks |
| T-Mobile | One Unlimited | $70 | Unlimited Essentials plan costs $60, but your speeds may be throttled |
| Verizon | 5GB | $55 | Unlimited options also available starting at $75 |
Many carriers provide rollover data, but shockingly few let you pay for only what you consume, making Google Fi’s pricing scheme pretty attractive. That said, if you’re one to burn through your data cap quickly, your monthly statement can get out of hand pretty fast. Thankfully, Google Fi offers a feature called Bill Protection designed to stop that.
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With Bill Protection, you aren't charged for additional data past a certain threshold. This effectively turns all Google Fi plans into unlimited data plans once you spend enough money. For example, under the current $10-per-gigabyte model, an individual stops getting charged for data after consuming 6GB, or the equivalent of $80 in one month.
Bill Protection is available for group plans too, though the amount you must consume before multi-line plans become "unlimited" is higher and differs depending on the number of lines active on your account. Google provides a calculator on the Fi website that breaks down how much subscribers could save in every circumstance.
If there's one downside, however, Bill Protection has forced Google to institute a soft cap on users who exceed 15GB in a billing cycle. Go over that limit, and you can continue to use the service and pay nothing, but your data speeds will be deprioritized. This is less than Verizon and AT&T's 22GB limit, or T-Mobile's 50GB limit.
Google recently added a more conventional unlimited plan to Fi's repertoire, which starts at $70 per month for one user, but can be as low as $45 per month if you have at least four lines on a group account. (Taxes and fees are not included.) Under this plan, each individual's data only slows after they've used 22GB. A Google One membership, which offers 100GB of cloud storage, is also included with unlimited accounts.
How Google Fi performs
Tom’s Guide has tested Google Fi on a number of devices over the past year. In our initial experience with the service, we used a Moto X4 Android One optimized for Google’s network. (That phone has since been dropped from the Google Fi store in favor of newer models.) Setup was a cinch thanks to the handy Google Fi app, which simply takes a Google account (i.e., a Gmail address) to begin. Add a payment method, choose whether you’d like to port a number or create a new one, restart your phone and voila — within minutes you’re up and running.
No matter what device we used, Fi’s service was as reliable and consistent as any major network we’ve tested.
The Moto X4 connected to T-Mobile’s LTE towers in New York City, according to network analytics app Signal Spy. A speed test displayed 19.5 Mbps downstream and 4.6 Mbps upstream. That’s consistent with what we’ve observed when testing T-Mobile LTE in the past.
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Setup and performance is similarly streamlined even if you bring a device to Fi that wasn’t designed for it, like an iPhone XS. The main difference is that you lose out on network switching, and you have to modify some APN settings to get SMS and MMS working properly. However, that doesn’t take long, and Google provides extensive directions with the Fi SIM kit and on its website to walk you through the process. (Fi only supports SIM-free setup on the Pixel 3 at the moment.)
BYOD devices on Fi are stuck on T-Mobile’s network, and don’t benefit from Sprint or U.S. Cellular’s infrastructures. Though in our experience testing speeds in a few locations around central New Jersey, that limitation didn’t make much of a difference.
Our Fi-connected iPhone XS averaged 61.2 Mbps for downloads and 7.7 Mbps for uploads, while our Pixel 3, also on Fi, topped out at 18.9 Mbps downstream and 2.7 upstream. The Pixel 3 curiously opted for Sprint’s towers over T-Mobile’s in many of these trials, even at times when the iPhone’s speed test results proved the Uncarrier’s data was flowing better.
To make the service a bit sweeter for iPhone users in particular, Google has recently added support for visual voicemail through the Fi iOS app. Previously, voicemail transcriptions would be delivered via text message — a clunky experience, albeit the only way Google could swiftly launch the service on Apple's handsets. Now, iPhone users on Fi can simply slide over to the Voicemail tab in the app and view and listen to all their missed connections there.
At this stage, it's unclear if Google intends to roll visual voicemail out for Android phones that aren't fully designed for Fi, like the Galaxy S10. However, the company did recently bring spam call warnings, the aforementioned VPN access and Wi-Fi calling to BYOD Android handsets, so it could happen eventually.
Ultimately, customers who take an iPhone or other unlocked device to Fi aren’t missing much without network switching — though, if you’re going to pay Google to use T-Mobile’s towers, you may as well consider T-Mobile’s plans to begin with (or those of its prepaid subsidiary, Metro), especially if you’re a heavy data user.
About the Google Fi app
No matter what device we used, Fi’s service was as reliable and consistent as any major network we’ve tested. But that’s not the whole story, because half of the network’s charm resides in its brilliantly designed app and overall customer experience.
We’re all painfully familiar with terribly designed carrier apps that hide simple features and information behind dated, clunky interfaces that are excruciating to navigate. Google Fi is a breath of fresh air, as you’d expect from the company that built Android.
Open the Google Fi app, and you're immediately presented with a bar displaying your data consumption, that you can preset with a warning to know when you’re getting too close to any self-imposed limits. Scroll down, and you’ll see an overview of your plan above easy links to alter everything from voicemail settings, to blocked numbers to the service address linked to your account.
Swipe to the right for Billing and Support tabs, where all your previous statements are easily viewable. Getting in touch with a representative is a snap, too, with options for phone, chat and email alongside estimated wait times. I received a response to a chat query in just 1 minute.
The app is such a pleasure to use, unless you have to enlist the expertise on Google’s wonderfully enlightening Google Fi forum, you’ll never need to leave it. But the most impressive part of Fi’s interface is the way it handles multiple phones and lines.
At one point, I pulled the SIM card out of our Moto X4 and placed it into a Pixel XL, and Fi was smart enough to know that not only was it in a different phone, but precisely what phone it was and how much data was consumed on it. You can even break down that information into graphs, where daily usage is tallied per device. It’s an impressive degree of detail that is typically absent for users on other carriers who frequently swap SIM cards and devices.
You can also order free data-only SIM cards from the Fi app that you can then place inside other devices, like tablets and laptops. The data consumed on those devices will simply be added to your monthly tally, without any extra fees or extra line charges, and Google doesn’t bill you extra for tethering from your Fi phone, either.
Should you use Google Fi?
Google Fi works well and has a great app — but how does it compare to the value offered by other networks? Despite the strength of three carriers, Google’s coverage map is smaller than Verizon’s, particularly in more rural areas.
When the conversation turns to price, however, things are a bit different. Verizon’s cheapest individual postpaid plan costs $55 for 5GB once autopay is enabled. On Google Fi, 3GB will run you $50. Although Big Red doesn’t only charge you for the data you use, it does allow you to carry over unused data from month to month.
Because Verizon was a longtime exclusive carrier partner for Google’s Pixel devices up until the most recent generation, comparisons against Google Fi are inevitable. But perhaps it’d be more appropriate to cast Google’s network against a less costly prepaid carrier.
Metro by T-Mobile is currently our favorite discount-service provider, offering T-Mobile’s speedy network for even lower prices. Customers can get 2GB for $30 per month, or 10GB for $40 — with taxes and fees included. Google Fi runs a whopping $70 for 5GB, though Metro leaves you with two caveats: tethering is not allowed, and all video streams are capped at 480p.
Fi is also great if you travel, offering international data and text for no added charge, and calls at 20 cents a minute. Metro has $5-per-month that extends coverage to Mexico and Canada, but its $10-per-month World Calling package is tremendously limited, providing only a paltry 200MB of data, 200 minutes and 200 texts.
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In the past, families didn't stand to benefit as much on Google Fi. Both Metro and Boost Mobile provide each user with their own data bucket, whereas with Fi's pay-what-you-use plan, every line’s data is shared. Now that there's an unlimited option, Fi can be significantly cheaper depending on the amount of people signed up. An individual will spend $70 a month, plus taxes and fees, for unlimited data; conversely, two people will pay $60 each, three people $50, and four $45. Each gets their own 22GB of full-speed data to use as well.
Bottom Line
Google Fi is by no means the cheapest carrier out there. If you eat up a lot of data, Google’s service can get quite expensive fast. Discounts on multiple lines are also modest compared with other prepaid carriers like Boost and Metro by T-Mobile, and unless you opt for the unlimited plan, everyone draws from the same pool of data on Google Fi.
Still, Google Fi offers a premium user experience, thanks to a competitive network map, great coverage for travelers, useful perks (for the devices that support them, at least) and software that is second to none. It’s the best mix of cost and convenience out there, with a simple pricing structure and properly designed app. And in wireless, those two things go very, very far.