The decision to use an eSIM or your operator's roaming might seem straightforward, but it can make a difference of €50 to €300 in just one week of travel. This comparative guide provides you with the real data to make an informed choice before you leave.
What is roaming and how does it work?
International roaming is the service your usual operator offers so you can use your number, calls, and data when you are outside the country. Your phone automatically connects to a local network at your destination, and your operator charges you for that usage.
Within the European Union, roaming is free for most Spanish tariffs — this is the famous "Roam like at Home" regulation in effect since 2017. But outside the EU, roaming costs can skyrocket: from €5/day for tariffs with an extra bonus, up to €15-€20/day without a bonus, or even charges per MB consumed in more exotic destinations.
The problem with roaming isn't just the price. It's the uncertainty: many travelers come home with unexpected bills of €80, €150, or more because they didn't read the fine print of their tariff.
What is a travel eSIM?
An eSIM (embedded SIM) is a chip integrated into your mobile phone that you can digitally program to connect to any operator in the world, without needing a physical card. Travel eSIMs, like those offered by PuraSIM, are prepaid data plans specific to a destination or region: you pay a fixed price, install the digital profile in seconds, and get unlimited data or a large volume without surprises.
More than 90% of smartphones launched since 2022 are eSIM compatible: iPhone XS onwards, Samsung Galaxy S20 onwards, Google Pixel 4 onwards, among many others.
eSIM vs. roaming: complete comparison table
| Factor | Operator Roaming | PuraSIM eSIM |
|---|---|---|
| Typical price | €5–€20/day (outside EU) | From €9 for the entire trip |
| Price in EU | Free (with fair usage limits) | Free (we recommend keeping your plan) |
| Surprise bill | Frequent outside EU | Impossible — fixed prepaid price |
| Coverage | Local networks via operator agreement | Local networks of the destination |
| Speed | 4G/LTE in most destinations | 4G/LTE or 5G depending on plan |
| Installation | Automatic (nothing to do) | Scan QR before leaving (2 min) |
| Keep your number | Yes | Yes (your SIM remains active in parallel) |
| Calls included | Generally yes | Data only (use WhatsApp/Facetime) |
| Multi-country travel | Expensive or complicated | Regional plans available |
| No contract | No — subject to your contract | Yes — fully prepaid |
Real price comparison: roaming vs. eSIM by destination
Let's look at concrete numbers. These are real prices from major Spanish operators compared to PuraSIM (July 2026):
Mexico — 7 days travel
- Movistar "Mundo": €5/day = €35 for 7 days
- Vodafone "Global Pass": €6/day = €42 for 7 days
- PuraSIM eSIM Mexico 10GB: from €12 total
Savings with eSIM: between €23 and €30 in just one week.
United States — 10 days
- Orange "Travel": €9/day = €90 for 10 days
- Movistar extra USA bonus: €60-€80 for 10 days
- PuraSIM eSIM USA 15GB: from €15 total
Savings with eSIM: up to €75 on a 10-day business trip.
Thailand — 14 days
- Standard Spanish operator: €10-€20/day without bonus = €140-€280
- PuraSIM eSIM Asia 20GB: from €18 total
The savings here can be literally 10 times the price of the eSIM.
When does it make sense to continue using roaming?
We won't tell you that eSIM always wins. There are cases where roaming is a better option:
- Travel within the EU: If your Spanish tariff includes free EU roaming (almost all since 2017), there's no point in spending on an eSIM. You're already covered.
- 1-2 day trips: For very short getaways, the daily roaming bonus can be convenient if you already have it activated and the price is reasonable.
- If you need incoming calls to your number: A travel eSIM only provides data. If you're expecting important calls to your Spanish number, you need your physical SIM to remain active — which is perfectly possible in Dual SIM mode.
- Phone without eSIM: If your mobile doesn't support eSIM (models generally older than 2020), roaming might be your only option without buying a local physical SIM.
When is an eSIM clearly better?
- Travel outside the EU for more than 3 days: the savings are immediate.
- Travel to multiple countries on the same route: a regional eSIM plan covers the entire area.
- If you use a lot of data: streaming, Google Maps without offline, video calls. Roaming bonuses run out quickly, and then they charge per MB.
- If you want total certainty about what you're going to spend before leaving.
- If you travel often: installing an eSIM takes 2 minutes from your sofa at home. It couldn't be more convenient.
The myth of "included" roaming in many tariffs
Many operators sell tariffs that claim to include "international roaming," but the devil is in the details. Read this before trusting your tariff:
- "Roaming included in EU" usually means you don't pay extra — within the limits of your plan.
- "Roaming bonus" usually gives 100-500 MB extra outside the EU, or 1-3 free days per year. It runs out very quickly.
- "Roaming data" without further specification might mean reduced speed (64Kbps or 128Kbps) — useless for Instagram or Maps.
The fine print of roaming is the number one reason why travelers with "roaming included" come home with surprise bills. With a prepaid eSIM, that's impossible: when the data runs out, it simply runs out. No automatic extra charges.
Dual SIM: the best of both worlds
The great advantage of eSIM that many don't know is that you can use Dual SIM: your usual physical SIM + the travel eSIM at the same time. This means:
- You continue to receive calls and SMS on your Spanish number (in case your bank, your boss, or family calls you)
- You use the cheap eSIM data for everything else
- Zero involuntary roaming — the mobile uses data only via the eSIM
To configure it: settings → Mobile data → select the travel eSIM as the default data line. Your number remains active for calls and SMS without consuming roaming data.
What data speed do travel eSIMs offer?
PuraSIM's eSIM connects to the main local networks at the destination — the same ones you would use by buying a physical SIM at the airport. In most countries, you will get:
- 4G LTE as a minimum — sufficient for any normal use
- 5G available in destinations like the USA, Mexico, Emirates, Japan
- Typical speeds: 20-100 Mbps download, more than enough for HD streaming, video calls, and Maps
Your operator's roaming usually offers the same technical coverage, but frequently limits speed to 4G or even 3G in some agreements with local operators.
Frequently asked questions: eSIM vs. roaming
Do I lose my number if I use an eSIM?
No. Your physical SIM keeps your number active in parallel. No one will notice that you are using data from another line.
Can I use the eSIM in several countries on the same trip?
Yes, as long as you choose a regional plan. PuraSIM offers plans for Latin America, Europe, Asia, and other regions that work in multiple countries without changing eSIM.
What happens if I run out of eSIM data?
You can buy another plan or activate the data on your Spanish SIM. There are no automatic extra charges.
Do I have to wait until I arrive at my destination to install the eSIM?
No, quite the opposite: install the eSIM at home before you leave, with comfortable WiFi. The profile downloads in 1-2 minutes. Then at the airport, you just have to activate it.
Does the eSIM work on an airplane?
During the flight, you activate airplane mode normally. Upon landing at your destination, you deactivate airplane mode, and the eSIM automatically connects to the local network.
Final verdict: eSIM or roaming?
For travel outside the European Union, eSIM consistently wins on price — with typical savings of €30 to €200 depending on the destination and duration. Roaming is convenient but expensive, and its "surprises" are the most frequent headache for the modern traveler.
If your phone is compatible (iPhone XS or later, Samsung S20 or later), eSIM is the smart choice for any international trip outside Europe. Predictable price, easy installation, equivalent coverage.
Do you already know which plan you need? Check our eSIM plans by destination and activate it from home before you leave.
