I used a Saily eSIM for the first time recently and it was revolutionary. Never going back to buying physical SIMs.
Being able to buy it in advance and activate it when the plane lands is great. Also fairly cheap.
Use this referral code to get $5 off: BENORI8447
You need to download their app here: https://saily.com/download-esim-app/
Saily eSIMs
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Saily eSIMs
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eMaxis Slim Shady
eMaxis Slim Shady

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Re: Saily eSIMs
I used Ubigi on my last trip to the States and had the same feeling - very convenient and dead simple.
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Re: Saily eSIMs
Can I ask an embarrassingly entry-level question?
If I use an eSIM on my phone when traveling overseas, does my regular phone number still work during that period?
If I use an eSIM on my phone when traveling overseas, does my regular phone number still work during that period?
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Re: Saily eSIMs
It depends. Nothing should get lost, but if your phone can't handle two sim cards at a time (irrespective of format) you would only be able to use one line at a time. In iOS for example, you have an easy-to-understand "switchboard" where you can switch each sim on and off. I think from iPhone 12 upwards, two can be active at a time. So you may chose.AreTheyTheLemmings? wrote: ↑Tue Mar 18, 2025 3:25 am If I use an eSIM on my phone when traveling overseas, does my regular phone number still work during that period?
I use one physical card and one eSim very often.
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Re: Saily eSIMs
On my phone (Pixel 7a) I have a setting that chooses which SIM to use (the physical one or the eSIM that is loaded).AreTheyTheLemmings? wrote: ↑Tue Mar 18, 2025 3:25 am Can I ask an embarrassingly entry-level question?
If I use an eSIM on my phone when traveling overseas, does my regular phone number still work during that period?
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eMaxis Slim Shady
eMaxis Slim Shady

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Re: Saily eSIMs
Telebroker wrote: ↑Tue Mar 18, 2025 4:43 am It depends. Nothing should get lost, but if your phone can't handle two sim cards at a time (irrespective of format) you would only be able to use one line at a time. In iOS for example, you have an easy-to-understand "switchboard" where you can switch each sim on and off. I think from iPhone 12 upwards, two can be active at a time. So you may chose.
I use one physical card and one eSim very often.
Thanks!RetireJapan wrote: ↑Tue Mar 18, 2025 4:48 am On my phone (Pixel 7a) I have a setting that chooses which SIM to use (the physical one or the eSIM that is loaded).
Re: Saily eSIMs
Whether you can continue to make and receive calls through your local Japan mobile number abroad does indeed depend on your phone hardware, but there may be additional factors: the particular cellular/radio technologies used in your destination (although these seem to be more standardized internationally these days), agreements between your local and destination carriers, and restrictions on the telephony plan you have with your provider. The cost of using your local number abroad can also vary significantly according to different circumstances. If you anticipate being critically dependent upon using your local number during a trip abroad, especially to a new destination, confirming capability and pricing with your carrier before departure would not be a bad idea.
Using inexpensive temporary eSIMs on short trips abroad is becoming increasingly convenient, but sometimes there can also be challenges with activation and very specific technical settings. Some carriers require specific APN settings, for example, and these are not always documented well by third-party providers. When I travel, I take offline copies of the provider's activation procedure and technical support contact info, and I try not to make my plans dependent upon being able to activate the eSIM immediately upon touchdown. Often it works without a hitch, but occasionally a bit of troubleshooting is required.
Using inexpensive temporary eSIMs on short trips abroad is becoming increasingly convenient, but sometimes there can also be challenges with activation and very specific technical settings. Some carriers require specific APN settings, for example, and these are not always documented well by third-party providers. When I travel, I take offline copies of the provider's activation procedure and technical support contact info, and I try not to make my plans dependent upon being able to activate the eSIM immediately upon touchdown. Often it works without a hitch, but occasionally a bit of troubleshooting is required.
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