How to Switch eSIM Providers Mid-Trip (If Your Plan Runs Out)

If your eSIM data runs out mid-trip or the connection just isn't holding up, you don't need to touch your original eSIM at all — buy a new eSIM from a different provider, such as co:sim, install it alongside the one already on your phone, switch your data line to the new one, and keep the old profile as a backup. No removal, no re-registering a device, no starting the trip's connectivity from scratch. This guide walks through when that's actually the right move versus a simple top-up, the exact steps to install a second eSIM while already traveling, and what to check before you buy.

#Before you switch: check these first

Is this actually a top-up situation instead? If the current eSIM's plan supports adding data and hasn't expired yet, a top-up is faster and keeps everything on one profile — no new QR code, no switching between lines. One travel-eSIM provider's own guidance frames it well: add-ons work when a plan still has time left and simply needs more data, while a genuinely new eSIM makes sense when the plan has expired, doesn't support add-ons, or the destination or data type needs to change entirely (Nomad's add-on vs. new eSIM guide).

Do you have Wi-Fi or a working connection right now? Buying and downloading a new eSIM requires an internet connection somewhere — a café, hotel lobby, or a friend's hotspot all work. Without any connection at all, this has to wait until one is available.

How many eSIMs can your phone actually run? Modern phones store several eSIM profiles, but the number that can be active for data at once is more limited — an iPhone 13 or later supports two eSIMs active simultaneously (in addition to standard Dual SIM with a physical card), but even then a phone "can use one cellular data network at a time," according to Apple's own support documentation (Apple: Use eSIM on iPhone). In practice that means installing a second eSIM is simple, but only one line carries data traffic at any moment — switching providers is a matter of choosing which line is active, not physically swapping anything.

#Step-by-step: installing a new eSIM from a different provider mid-trip

1. Find any working connection. Hotel Wi-Fi, a café, or a hotspot from a travel companion — the purchase and download both need real internet access.
2. Buy the new plan. Pick a data-only plan for the destination or region actually needed — a co:sim eSIM for Thailand is one example of a specific destination page, though any current location works the same way; the QR code arrives by email within seconds of payment.
3. Leave the old eSIM installed. Don't delete it — most eSIM apps distinguish between deactivating (reversible, keeps the profile for later) and deleting (permanent), and deleting is generally only recommended once a destination won't be revisited and the plan has no top-up option left, per guidance travel-eSIM providers give their own users on this exact question (Airalo's own guide on changing an eSIM plan).
4. Install the new eSIM as an additional line. On iPhone: Settings → Cellular → Add eSIM, scan the new QR code. On Android: Settings → Network & Internet → SIMs → Add eSIM, same process.
5. Set the new eSIM as the active data line. Turn on data roaming for the new line and turn off data (or fully deactivate) the old one, so the phone doesn't try to use both or rack up unexpected charges on the original plan.
6. Confirm it's working before relying on it — load a webpage or check a maps app to verify the new line is actually carrying data, not just installed.

#If something goes wrong

No Wi-Fi anywhere nearby. This is the one real blocker — buying a new eSIM needs some internet connection first. A hotel front desk, a nearby restaurant, or even brief public transit Wi-Fi is usually enough for the few minutes a purchase and download take.

The new eSIM won't activate. Double-check data roaming is turned on specifically for the new line, and that it's set as the primary line for cellular data (not just installed but inactive). Restarting the phone after installation resolves most activation hangs.

The old provider keeps using data or racking up charges. Fully deactivate the old eSIM's data (not just switch the default line) if there's any risk of dual charges — some phones will fail over to a secondary active line if the primary one has no signal, which isn't what's wanted when deliberately switching away from an underperforming network.

#FAQ

#Should I keep my old eSIM installed as a backup?

Generally yes, as long as it still has a working profile and hasn't been deleted. Keeping it deactivated rather than removed means it's available instantly if the new provider also has a bad day in a particular region — a real, common reason travelers carry two active providers rather than relying on just one for an entire trip. Most phones handle several stored eSIMs without issue; the practical limit is how many can carry data at once (commonly one or two, depending on the phone), not how many can simply sit installed and ready in the background. There's no cost to leaving an unused, deactivated eSIM on the device — a co:sim eSIM installed as a backup alongside another provider's plan works exactly the same way, ready to switch to the moment it's actually needed rather than sitting idle for nothing.

#Do I lose unused data if I switch to a new provider?

Usually yes, if switching means abandoning the old plan rather than topping it up — prepaid travel eSIM data generally doesn't transfer between providers or roll over once a plan's validity period ends, and no provider, co:sim included, can add data to a different company's plan. That's exactly why checking for a top-up option first matters: if the current plan still has time left and just needs more data, adding to it keeps every remaining gigabyte instead of starting over on a new provider's plan. If the old plan is genuinely finished — expired, or with no add-on support left — there's nothing left to lose by moving on, and a fresh data-only eSIM installs just as quickly mid-trip as it would have before departure.

#Can I run two eSIMs from different providers on the same phone at once?

Yes, for storage — most modern phones can store multiple eSIM profiles from entirely different providers with no conflict, and mixing brands (a co:sim plan alongside a different provider's plan, for instance) causes no technical issue either way. What's more limited is how many can be active for data simultaneously: recent iPhones support two active eSIMs together, but the phone still only routes cellular data through one line at a time, according to Apple's own documentation. Android devices vary more by manufacturer and model, so it's worth checking a specific phone's SIM settings menu to see how many lines it can run active at once. Either way, switching which provider is actually carrying data at a given moment is just a toggle in settings, not a full reinstall or a second registration process.

#How do I know if it's my eSIM or the local network that's underperforming?

Try loading a simple, low-data page like a basic search engine first — if that consistently times out in a specific area but has worked fine elsewhere on the same trip, it's more likely the local network coverage than the eSIM itself. If speeds are fine in one location but the connection drops out entirely, checking a maps app or another traveler's device on a different network can confirm whether it's a broader area issue. When performance is consistently poor across an entire trip rather than one specific location, installing a second eSIM from a different provider as a backup — without deleting the first — is a low-risk way to compare the two side by side.

Buying a co:sim data-only eSIM works the same way mid-trip as before departure — pick a plan, get the QR code by email, and install it alongside whatever's already on the phone.