When you run out of data on most travel eSIMs, the process goes like this: buy a new plan, receive a new QR code by email, find a second device to display the QR code on (because you can't scan your own screen), go into your phone settings, delete the old eSIM profile, scan the new one, wait for activation. Ten minutes on a good day. Thirty minutes if anything goes wrong.
Driftvoy works differently. You buy a top-up, the data gets added to your existing eSIM, and you're back online. No new QR code, no reinstall, no second device needed.
Here's why that's possible and why it's not the default.
What an ICCID actually is
Every SIM — physical or eSIM — has an ICCID: a 19–22 digit number that permanently identifies that specific SIM card profile. It's analogous to a MAC address on a network card. It doesn't change, it's globally unique, and it's how the carrier network recognizes your device.
When you install an eSIM profile on your phone, that profile gets bound to an ICCID. The profile lives on your phone's eUICC chip (the embedded SIM hardware). The ICCID is the identifier the carrier uses to route data to your device.
How a top-up without reinstall actually works
A "same-ICCID top-up" means the carrier adds a new data package — more gigabytes, a new validity window — to an existing ICCID rather than issuing a new eSIM profile.
From the network's side: the ICCID is still active, still authenticated, still connected. There's no re-provisioning step needed. The data balance just increases.
From your phone's side: nothing changes. The eSIM profile was already installed. The new data shows up as available balance on the same line.
The technical requirement is that the upstream provider has to support this at the provisioning level. Not all wholesale eSIM providers support same-ICCID top-ups — some issue a new ICCID for every purchase by design, which is simpler to implement. Our upstream provider supports top-ups on the same ICCID, which is why Driftvoy can offer this.
There's a limit: up to 10 top-ups per ICCID. After that, the profile has to be replaced. For most travelers, 10 top-ups is more than enough — that's roughly 8–12 months of monthly top-ups before you'd need a new eSIM.
Why most providers still issue new QR codes
A few reasons:
Simplicity of implementation. If you issue a new eSIM profile for every purchase, you don't need to track ICCID state across top-ups. Every order is a fresh provisioning event. It's a simpler system to build and debug.
Upstream limitations. Many wholesale eSIM providers don't support same-ICCID top-ups. The provider's hands are tied by whatever the backend can do.
Business incentives aren't strongly aligned. Top-up friction is annoying for the customer but not fatal. Most travelers tolerate it. Reducing top-up friction is a quality-of-life improvement, not a survival issue for the provider.
When it actually matters
For a week-long trip where you buy one plan and use it, same-ICCID top-up is irrelevant. You're not topping up.
Where it matters:
Longer trips. If you're doing a month in Japan and buying two or three plans over the course of the trip, reinstalling your eSIM each time is genuinely annoying. Same-ICCID means you top up from your account and keep going.
Frequent travelers. Someone who goes to Japan twice a year would reinstall their Driftvoy Japan eSIM once — then top up for every subsequent trip as long as they don't delete the profile.
Situations where you don't have a second device. Scanning a QR code requires seeing it on one device while scanning with another. If you're traveling solo with one phone and your laptop isn't with you, reinstalling is complicated. With same-ICCID top-up, you never need to do it.
What "up to 10 top-ups per ICCID" means in practice
The limit is 10 top-up events — not 10 GB. If you buy a 10 GB plan and then add a 20 GB top-up, that's one top-up used.
After 10 top-ups, the ICCID can't accept more packages. At that point, you need a new eSIM profile. We'll proactively send you a new one before you hit the limit — you won't hit it by surprise.
For a traveler who goes to Japan once or twice a year and does one or two top-ups per trip, you'd reach the limit after 5–10 trips. By then, eSIM technology will probably have moved on anyway.
The short version
Same-ICCID top-up means the carrier adds data to your existing eSIM profile instead of issuing a new one. You don't reinstall anything. You just have more data. It works because our upstream provider supports top-ups at the provisioning level, and because your phone's eUICC chip keeps the profile stored permanently until you manually delete it.
It's a small thing that becomes a meaningful thing over time.
Driftvoy plans support same-ICCID top-up on all Japan and Thailand SKUs except the Thailand 50GB / 10 Days Launch Deal (which is not reloadable by design). See all plans →