T-mobile (unlocked) iPhone 5SE will not work internationally?

T-mobile (unlocked) iPhone 5SE will not work internationally (japan & SE Asia)??


My current old t-mobile iPhone 5S* has worked fine (for me) in the USA and while traveling around the world (Hong Kong, Japan, etc) all without issue. I wish to buy to an iPhone 5SE but it appears model A1662 (the t-mobile model sold from apples retail USA website) will not work anywhere outside the USA!?!??!!


I’m in Japan currently and can buy the 5SE that’s sold here… the model number is different than the USA t-mobile iPhone SE sold from apples website, I believe the Japan SE model is A1723 (see here: http://www.apple.com/iphone/LTE/). I just don’t want to buy this Japanese iPhone 5SE, return home, and have a phone that won’t work on t-mobile, or worse; maybe not work at all anywhere (since i’m always using t-mobile sim card not domestic sim card from country’s I’m traveling, maybe somehow t-mobile sim won't recognize Japan 5SE phone?).


It’s imperative I’m able to travel with my “t-mobile-sim-card-using-phone“ and have it WORK most places (in SE asia specifically). My 5S does this fine, but apparently the SE is a downgrade in this regard. Do I not have a proper understanding of all this, am I missing something??


TL;DR …Which iPhone SE model will work both domestically on t-mobile in USA and also internationally (primarily SE asia).

14 replies

Userlevel 5

You need to know which frequencies (bands) are being used on the carrier(s) you are trying to connect to, then check them against the bands that your phone supports. Not all iPhones are created equal, and some support more bands than others.

Not helpful.

Traveling internationally, there's a million and one carriers, it's even more complex when hitting multiple countries in short periods. My 5S just works, it's great, it's never a worry.

The 5SE apparently will not and that's stupid considering one of T-mobile's main selling points is: "easy international travel with our carrier".

Userlevel 5

I'm sorry if you find it unhelpful, but since when does T-Mobile control which bands a phone uses? I could take an old flip phone, slip my SIM card in it, and complain that it doesn't work in country X, but that doesn't change the bands that the phone receives or does not receive.

To simplify the matter, perhaps the purchase of a local SIM card should be in order? In any case, enjoy your trip.

I'm not interested on your personal feelings on on the matter. Please answer the original question:

TL;DR …Which iPhone SE model will work both domestically on t-mobile in USA and also internationally (primarily SE asia).

Userlevel 7
Badge +12

You could compare the spectrum support for both and see if they match

1700/2100, and 1900 for both 3G and 4G on T-Mobile. All GSM iphones will have 2G support.

If it isn't working it may be due to the device not being unlocked. Also I believe if you buy a Japanese version you may need to request an unlock as well.

This is from Apple's website;

Model A1723*

LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 17, 18, 19, 20, 25, 26, 28)

TD‑LTE (Bands 38, 39, 40, 41)

TD‑SCDMA 1900 (F), 2000 (A)

CDMA EV‑DO Rev. A (800, 1700/2100, 1900, 2100 MHz)

UMTS/HSPA+/DC‑HSDPA (850, 900, 1700/2100, 1900, 2100 MHz)

GSM/EDGE (850, 900, 1800, 1900 MHz)

Based on this the 1723 model does have the required frequencies to work on the T-Mobile US network. I have bolded the frequencies that T-Mobile US uses.

When roaming international T-Mobile does have a link to show what markets it phones they sell whether they should work.  You can input your country you are traveling to and then after selected scroll down and enter your device.  Japan is a unique market and often has models that are for primary use in Japan as they do have some unique bands than the ROW.

International Plans | Traveling Abroad without Roaming Fees | T-Mobile

The A1723 model (the Japan model) will work in Japan (obviously) and will also work on domestic USA t-mobile when I return, correct? But there is some question of whether the A1662 (usa t-mobile version) will work in Japan and most elsewhere in SE asia.... hmmm, ok.

Basically, this; is there any reason for me to NOT purchase the A1723 (Japan) model (assuming it's unlocked of course)? I'm stupid and really need this spelled out for me at a 5th grade level.

P.S. The link I provided earlier to the antenna models list shows two Japan A1723 versions, one listed as (GSM) the other (CDMA). I guess I get a choice at the store? Which do I want?

Userlevel 7
Badge +12

Can't say without knowing what frequencies are required for the carrier you are using in Japan.

Userlevel 7
Badge +12

GSM That is what T-Mobile uses

I'm a bit confused. The A1662 is the iPhone SE. I don't think there has ever been a "5" associated with that model. The A1662 has UMTS 2100 (band 1), which is the minimum required to roam in Japan, S. Korea and Singapore, plus quad-band GSM to roam everywhere else. It also has a whole lot of LTE bands including several used internationally, including Japan. Why would you think it would not work outside the US?

P.S. Don't look at the network specs for this phone on T-Mobile's website. Someone needs to go back and redo those when they are sober.

To clarifiy: "iPhone SE" or "iPhone 5SE" the two are used interchangeably--we're talking about the same thing: the SE model. You seem to be saying the A1662 (Tmobile USA apple store version) will work in Japan and Singapore because it does have the minimum band. I'm guessing coverage will be spotty or slow or something? I'm not sure if I understand the consequence here of having 'only the minimum band'.

And if anyone knows the answer to this:

Is there any reason for me to NOT purchase the A1723 (Japan) model (assuming it's unlocked)?

Here's a run down of some of the A1662's LTE Bands:

1) Used in Asia, including Japan

2/25) Used by T-Mobile, Sprint and other US carriers

3) Used in parts of Asia

4) Used by T-Mobile

5) Used by T-Mobile and in S. Korea

8) Used in Japan and S. Korea

12/17) Used by T-Mobile and AT&T

13) Used by Verizon

18/19/26) Used by Au & Docomo in Japan

20) Used in Europe and some Mideastern counties

29) Used by AT&T

So it has plenty of compatibility with Japan's LTE bands. Far more than minimally compatible. Unless you buy T-Mobile high-speed data passes, you'll only be getting about 128 kbps.

It is extremely difficult for a non-resident gaijin to buy prepaid mobile service in Japan.

Alright, if I buy the A1723 japan model here in Japan and then take it back to USA.... will it work on mobile?

Can't think of any reason why not but if you should ever want to port to Verizon, it doesn't have band 13. I'm not arguing against getting the A1723, just against the notion that the A1662 won't work in Japan.