(*UPDATED*) How to unlock au by KDDI Japanese carrier locked iPhone 5S

UPDATE 3: It is now April 2017 and I have been using my unlocked iPhone 5S for the past year without any problems in Singapore, with a Singapore-network SIM card.

UPDATE 2:  In March 2016, I attempted to use a so-net data-only sim in Japan with my iPhone 5S. It did not work, stating that the sim card was not a type compatible with my phone due to it’s settings (unlock settings?) and to contact my carrier about it.

UPDATE: As of 7 January 2016, my phone is finally unlocked! I am using a Singapore prepaid sim card from StarHub which works on the phone.

iPhoneIMEI.net contacted me after finding this post and let me try their service. They will do a factory unlock for your phone using your IMEI code. I was a bit skeptical but was reassured it would work 100%. Their customer service was fast and friendly.

After submitting my IMEI code, it took 3 days (of a possible 1 to 20) before I received an email saying my phone has been unlocked! All I had to do then was plug my phone into iTunes.

I did an iTunes sync but nothing seemed to happen, then updated my phone to the latest iOS. No visible change, so I borrowed a different carrier’s SIM card from a friend to test. Hey – it works on my phone! The incompatibility notice didn’t pop up and the phone got signal and 3G.

I’m so glad this is all over. I can finally use my phone back in Singapore! Still a tad worried until that SG SIM card works but I’m just a paranoid person.

The iPhoneIMEI service for Japan’s au by KDDI costs about £50 (8,500yen/USD72, exchange rates published at time of writing and may differ). You can read other reviews here.

Please note that the Shutter Sound will still remain on your phone. I haven’t found a way to make it disappear.

*** Previously written post below ***

Here is the simple answer: YOU CAN’T.  Well, not legally anyway. (Yet?*)

Edit 2: I asked around about the R-sim. It supposedly only works overseas with an overseas sim card, and you will need one on hand to activate it. A friend told me he tried it and the reception etc was horrible, others seem to recommend it. Go to the electronic town in your area (Akihabara, Den Den Town etc) or get it off Amazon. Never tried personally so I don’t know.

Edit: I’ve found a few online unlock sites that will do a factory reset for you but it will set you back up to $250. One site I asked is unable to unlock au phones as they use CDMA technology which can rarely be unlocked.

au won’t do it. The Apple store won’t do it. No matter how many times you ask au, or even if you’ve cancelled/ended your contract and paid for the phone in full THEY WON’T DO IT.

The Japanese Apple store staff took 20 minutes to explain to me that only sim-free phones sold at their store could work with foreign sim cards. He stated that “foreign sim cards might destroy your phone” or cause it to function weirdly, not be compatible bla bla bla then said I should just buy a new sim-free phone from them. EXCUSE YOU, I AM NOT MADE OF MONEY.

One non-Japanese staff at au told me point blank to go find some store to illegally unlock it. “Other Taiwanese and Chinese customers did that”, she said, “but well, you’d have to find a reputable store”.

“Your phone can now only be used as an iPod touch”, the staff chirped joyously, oblivious to my anguish, when I asked on another visit. “You know, it’s just as good as long as you have wifi!” EXCEPT IT IS USELESS AS A PHONE THANK YOU VERY MUCH. And it’s not like I radiate a wifi hotspot naturally y’know?

I pleaded with them. Told them I was leaving Japan (帰国する kikoku suru), reasoned that since I’d be cancelling my contract (解約 kaiyaku) hey, I paid for and now own this phone I WILL PAY YOU TO UNLOCK IT. It is a waste (mottainai) to get a brand new phone because my iPhone still works perfectly fine (2 min after I wrote this I dropped my phone and it ricocheted off the side of the wall and hit the floor BUT IT IS STILL OK) also I AM NOT MADE OF MONEY and phones do not fall from the sky.

Based on this Japan Times article, carriers are supposed to get rid of the SIM lock*, but it seems they won’t do so for iPhones or only sell certain handset models SIM free. Which is just as useless as ever.

I should have probably jumped to another carrier when my first contract with au ended but I liked au and preferred to stay naively, only to have them end my student fee wavers (it only applies for a maximum of 3 years supposedly) and give me endless headaches with this SIM lock issue. But I suppose any other carrier would have said the same thing.

I’ve also just paid over $600 in total for cancellation fees and the rest of the payments for my iPhone. This beats paying almost 10,000yen ($100) a month for a phone that DOES NOT WORK AT ALL OVERSEAS since I’ll mostly be out of Japan before the period my contract ends. If I want to use my phone (aka actually get any RECEPTION) it will cost me 2,000yen ($20) a day. How about No.

They do not accept payment via credit card. It’s cash only or a direct bank withdrawal (if you had been paying your bills that way) but hey I had $0 in my bank after all the shipping and moving out fees. So I had to switch my payment method to credit card which takes like, a week or some other really long time to take effect.

Also, just a heads up when you cancel your contract it happens immediately. You can’t cancel in advance (since you’re still paying for any usage in that month anyway) or have it cancel at the end of the month.

I was leaving Japan on 1 July, and thought they could automatically cancel it on the 30th but noooooooooo it doesn’t work that way. I ended up rushing over at 8pm on the 30th for them to cancel my phone contract and it immediately stopped working. You know, mobile data would have been a great solution for all the trouble I had at the airport the next day…..


Online “unlock your iPhone bla bla bla” places didn’t seem to be able to provide their service for a Japanese carrier locked one. Bleh. Some forums advice to jailbreak your phone. Nuh uh that doesn’t work.

Shops I’ve asked here in Singapore won’t do it, say they can’t do, it so now my 1.5 year old iPhone 5S has now become an iPod touch. Great.

So, keep this in mind before you sign that contract with a Japanese carrier. Buying a contract-free, SIM-free iPhone from the Apple Store will be a better choice that will save you much, much, trouble later on.

*note: Based on this post on Japan Mobile Tech, KDDI and Docomo phones WILL be unlocked, under certain conditions, but this is only applicable for phones that go on sale after May 2015. Thus meaning it does not apply yet to the iPhones which were already released before the new law came into effect.


  1. Audiego says:

    I found this blog on my fb’s timeline. I am also a user of AU KDDI locked iPhone 5s bought in japan last year. I returned to Indonesia after graduation and using those phone normally until today. The magic is the usage of ‘R-sim 10’ chip which software unlocked the phone. I can make phone call, message and 3G internet on 3G sim card, but there are some flaws such as can’t use phone call and internet on 4G sim (although some people on the internet can) and can’t use USSD code (code with * and # sign). I think you should try this method, as it’s quite cheap (I bought the chip on Japan for 2000 yen, and in my country this chip priced at 100000-200000 rupiah). You can check the instruction on https://www.youtube.com/watch?v=_9vJqQQVP8c

  2. nobu says:

    I am japanese and I am at UK now and I upgraded to iOS9 and find out I need an active SIM with my Iphone5 to activate my phone . I have already finished my contract and I only have locked iphone5, old KDDI sim. I called Apple UK and they said only the activation here is you need to talk to KDDI and unlocked! I called KDDI, they said you are using Iphone from Japan so I can’t support you if you are in oversea.
    right now my iphone is just metal object. I can take screenshot of Hello screen and I can browse iphoto. but I can’t used anything else.
    I am not going back to Japan for while so I have no idea what to do with it!

  3. tokyo_girl says:

    It’s so exasperating… I fixed a broken screen thinking I could use the old phone overseas… seems not… what a pain in the butt.

  4. AL says:

    I just saw your post as I was looking for a way to use my AU iphone 5s in my home country once I leave Japan for good later this year. I still have a couple of months left in Japan. I’d like to know for sure if there is a way to use my phone after that, so I was thinking of trying to unlock it before I leave. Do you know if this would affect it working fine in Japan? I am guessing that it has to remove the carrier settings which block other carriers from working properly with the phone and since the carrier settings are what makes it work sim-free and recognize the carrier in Japan, I have a feeling it would create problems while in Japan. What do you think?

    • Bernie Low (beanmylife) says:

      I’m sorry I’m not too sure about if the au sim still works after unlocking. I unlocked after cancelling my contract and I don’t remember if the au sim showed having any service bars etc, and am also unable to check. It did work with my friend’s docomo SIM card so it can still both work in and out of Japan.

      By theory it should work perfectly fine, the service does a factory reset to the phone. Which supposedly just resets it back to before any carrier locks were done? I’m not too sure on the technical details.

  5. Pui San says:

    Thanks for the useful post!
    I am finding way to unlock my Iphone 5s under Japan’s AU by KDDI as well, which is exactly the same condition as yours I assume. However, iPhoneIMEI.net charge me $98 instead of $72 when I estimated the price. Is this normal?
    Meanwhile, I have looked through service by other companies and found out that some tricky companies have hidden payment. May I know IPhoneIMEI.net has any other hidden payment?
    Your reply will be much helpful. Thanks again for the post! Have a good day 🙂

    • Bernie Low says:

      Hello! You’d have to check with iPhoneIMEI.net about that. I’m not affiliated to the company besides this review so I wouldn’t know about their payment system etc.

      Hope that helps!

  6. Maia says:

    This is somewhat unrelated to the SIM-lock issue, but seeing that your iPhone 5s was bought in Japan I’m assuming your phone also had the mandated shutter sound lock on it too. After unlocking it and now being able to use it back home, does your phone still have this problem? I’m now back in the US and using my old iPhone 5 but would like to use the iPhone 5s I bought in Japan instead. I’m considering using the SIM unlock services to do it but wonder if it’s all even worth it since the shutter sound may still be there. I absolutely hate this feature about Japanese smartphones and don’t know if there’s a way around it. I’m sure for some people this isn’t really an issue but have this been a problem for you and have you found any way around it?

    • Bernie Low says:

      Hello Maia,

      Unfortunately, there is no work around on the shutter sound. I’ve been using my phone and no matter what it still has that annoying shutter sound :< I've resorted to using 'silent camera' apps but those almost always reduce the quality of the photo. It really might not be worth it to invest in the SIM unlock, perhaps getting a new phone altogether in the US would be a wiser choice.

    • Bernie Low says:

      Hi, yes mine works.
      Another reader commented that he had troubles activating his iPhone to work after the reset so it’s really up to you if you’d like to try.

  7. j says:

    These people are dishonest. They said my phone was blacklisted and I know for a fact that it wasn’t so I paid $56 for them to unlock and they did absolutely nothing but steal my money. Buyer beware!! Do not use them. Read the reviews below. I’m not the only one.
    They refused to give me my money back after I explained to them that my phone had shattered into pieces so I had no use of the unlock. This was in the first hour!!! They lied and said that they had already “tried to unlock it” Buyer….run…as far away from these people as possible!!!

  8. charles rivera says:

    Dear Bernie,

    Thank you so much for recommending the link: https://iphoneimei.net/

    I found the site before reading your blog and was so desperate to use their services. BUT I was skeptical and cautious. Do you know if their SIM unlock will work in the US? Thanks for any advice!


  9. long says:

    I’m Vietnamese and i offer you buy an heicard sim to use every where, you can buy it on dh gate (about 7 usd) connect your sim with it and use,

  10. santosh says:

    i have a iphone 5 which is bought from japan..i unlock this phone in nepal and it is not supporting the new sim card and the 3G sim of Nepaltelecom bt it support all type of sim card of NCELL..why?

  11. sabarigiri says:

    I am from india. I have kddi iphone6 bought an year ago close to October 2015. past one year I have been using with help of rsim10. One week back I just removed my sim and insert it with another airtel sim with rsim. Now i am not able to use my iphone6. Its shows activation required and sim card not valid. Please help me to unlock my iphone6. There are unlocking sites. But I can’t believe which one will work and I don’t want waste my money on spammers.Please help me guys. thanks in advance.

  12. chiru says:

    iPhoneIMEI.net is a scam sites don’t go and buy any unlock from their end. I got Response As we have already prepared your unlock and incurred the unlocking charge, we cannot issue a card refund for handsets which are rejected in such circumstances.
    I was shocked cos I checked it with their link and am sure the my devices have clean imei’s.
    Please find below URL http://www.imeipro.info/report.html?token=d80ce247061c4f8d9fefec4c2dc3bc5b

    Ive already paid £19 for pre order and £65 for the whole unlock for my iphone 5S.

    Now they are not at all responding my Email also, This guys are scammers,please don’t take any order from them.

  13. jucell says:

    hi. good morning i’m also a user of iPhone 5s from japan. & i’m here in the Phil.my phone is already unlock. so that i can use Phil sim card like TM or “touch mobile” under GLOBE but. this past few days my internet connection didn’t work fast. i cant connect to any wifi server at the same time. i also deleted my APN acct. please help me guys
    thanks in advance

  14. Kirstie says:

    Hi! I noticed your March 2016 update that you tried to use your phone in Japan and it didn’t work? Most of the unlocking services online (paid), I found that they say they will completely unlock the phone but it will no longer work in Japan 🙁 were you able to use the phone again after leaving Japan?

    • Bernie Low says:

      Hi Kirstie,
      I was unable to use it in Japan with a prepaid-sim card (meant for tourists). I didn’t try with other Japan SIM cards but my phone works completely fine outside of Japan.

      I have used it for more than a year now since I’m back in Singapore with no issues at all.

      Hope that helps!

      – Bernie

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