Effective from 16 October 2026. We reserve the right to change these terms — but the version in force when you completed your order is always the one that governs it (see section 15).
1. Who we are
SemperOnline is operated by DataYield, s.r.o., a limited liability company registered in the Czech Republic, company number 11942649, VAT number CZ11942649, registered office Příčná 1892/4, 110 00 Praha 1, Czech Republic, entered in the Commercial Register kept by the Municipal Court in Prague, section C, insert 356047.
We are registered for VAT.
Contact: support@semperonline.com. We answer in English and Czech.
2. What we sell
We sell two things: data plans for eSIM and VPN access. You can buy either on its own or both in one order. Neither is a physical good — nothing is shipped; both are digital content delivered electronically, usually within a minute of payment.
Data plans for eSIM
A profile you install on your phone from a QR code or an installation link, together with a prepaid amount of data in named countries for a named period.
The connection itself comes from mobile operators in the country you are in, under agreements held by our supplier. What we owe you is what we promised: that the profile arrives, that it works, and that it has the parameters shown on the plan. Coverage, speed and signal in a particular spot are the operator's and your phone's business, not ours.
VPN access
An account on a network through which you can route your internet connection encrypted. We sell it for a fixed number of days, one-off or as a subscription (clause 7). You get credentials for an app and a QR code for setting it up by hand; how to switch it on is at /support/vpn-setup.
The network is run by a third party, not by us. We do not operate it, we have no say in where the servers stand or how they are configured, and the choice of countries may change. What we owe you is that the access arrives and works for the period you paid for.
What the network operator says it does not keep — browsing history, DNS queries, traffic content, source IP addresses, connection times or session lengths — is set out here as they state it. It is their policy, not our promise: we cannot verify it.
The app you connect with is published by another company and using it is governed by their terms, not these. You can also connect without it, with a QR code in a tool of your own choosing.
What governs these terms
We are not a provider of electronic communications services under the Czech Electronic Communications Act. We run no network and hold no contracts with operators — we sell digital content and broker access to someone else's network. These terms are therefore governed by the Civil Code, not by § 63 of that Act.
3. What you need for it to work
- A phone that supports eSIM and is not carrier-locked. The list is at
/support/compatibility. Check before you buy: an unused eSIM can be returned, a used one cannot. - An internet connection when you install it. The profile is downloaded over the internet; without a connection it cannot be installed.
- On some plans, data roaming switched on in your phone's settings.
For VPN you need a device running a supported system — the app runs on Windows, macOS, iOS, Android, Android TV and Fire TV, and the QR code works in other tools too. One access can be signed in on up to ten devices at once.
4. How the contract is made
What you see on the site is an invitation, not a binding offer; your order is the binding part. The contract is made when we accept your payment, and from that moment we owe you what you ordered.
A subscription creates a recurring payment, not a one-off one. What that means and how to stop it is in clause 7.
You can buy without an account. Either way we need a working e-mail address that belongs to you, because that is where the activation code and the receipt go.
We confirm every order by e-mail, with the QR code, the installation link and a summary of what you bought.
5. Prices and payment
Prices shown on the site are final and include VAT. The amount on the payment screen is the amount taken: the tax comes out of it rather than being added to it.
The rate follows the country you are buying from, and the tax document sets it out separately. Buying as a business with a valid VAT number in another EU member state, enter it on the payment screen: the reverse charge applies and the VAT comes off the total.
We sell in several currencies and you pay in the one selected on the site. Which ones those are is shown in the currency switcher — the list changes over time, and these terms deliberately do not name them, so that they never promise a currency we no longer offer. Anything you have already bought is unaffected by a change to the list. The price in each currency is our own, not a conversion bolted on at the end of the payment — the amount on the payment screen is the amount taken, with no exchange mark-up from us or from the payment provider. What your bank does between your card and its own currency is between you and your bank.
You can switch currency until you start paying. An order already under way keeps the currency it was created in.
Payments are handled by Stripe. Your card number never reaches us.
Receipts are issued electronically and sit in your account next to the order.
Plan prices change over time. Yours is the price shown when you completed the order; a later change to the catalogue does not touch it.
6. Delivery
We deliver electronically, usually within a minute of payment, to the e-mail on the order and to your account.
If delivery fails — our fault or the supplier's — we keep retrying on our own. If it has not worked within 24 hours of payment, we refund you in full without you having to ask, and we write to tell you. The money goes back the way it came; your bank usually shows it in 5–10 working days.
If a profile was created at the supplier in the meantime, we finish it by hand and come to you — that case deserves a person looking at it.
The activation code is single-use: a profile can normally be downloaded only once. Delete it from your phone and it cannot be reinstalled; you would need to buy a new eSIM. So do not forward your QR code to anyone.
VPN access is delivered the same way and in the same time. If it cannot be set up, we refund the price of that access and the rest of the order goes on — an eSIM bought alongside it is not held up.
7. Validity, top-ups and subscriptions
eSIM: validity and top-ups
Each plan states how long it lasts. When the clock starts differs by plan — for some it is installation, for others the first connection to a network. It is written on the plan and on your eSIM's detail page.
Unused data is not refunded or carried over once validity ends, except as below.
A top-up adds data and extends validity, including for data you still have left, as long as it has not expired. We show you the exact terms before you confirm.
VPN: validity
VPN access lasts for the number of days you bought. The last day it works is shown in your account; after it the account is switched off. Unused days are neither refunded nor carried over.
VPN: subscriptions
VPN can also be bought as a subscription — you pay repeatedly and the access renews itself until you cancel. We show you the length of the period and the amount to be charged before you order.
- It renews on its own, at the same time of day the subscription began.
- The price is frozen on your subscription. If we change the price list, your renewals carry on at the price you signed up at.
- You can cancel at any time — in your account, or with the link in every subscription e-mail. That link works without signing in, so do not forward it to anyone.
- Cancelling takes effect at the end of the period already paid for. Until then the access keeps working, and no pro-rata part is refunded.
- If a renewal does not go through, the access stops working after the last paid day. It is not gone at once — pay and the same account comes back.
- You can hold more than one subscription; each is a separate access.
8. Fair use
Plans are for ordinary personal use while travelling. They are not for permanent connectivity at a fixed address, for resale, or for sharing with dozens of devices.
Operators may slow the connection when usage is heavy (FUP); where that applies, it is stated on the plan.
We will block a profile, without prior warning, if you:
- use the plan for permanent connectivity at one fixed place rather than for connectivity while travelling,
- resell the connection or provide it to other people,
- or use it unlawfully or for fraud.
Where we block for those reasons, unused data and remaining validity are forfeited and the price is not refunded.
For VPN the same applies, plus the network operator's own rules: the access is for your own devices, not for resale or for sharing with strangers, and it must not be used for anything unlawful. The network operator can block it too; we will tell you what happened, but the decision is not ours.
9. Cancellation, complaints and refunds
These are covered by a separate document, Refunds and complaints, which forms part of these terms. In short:
- An unused eSIM can be returned within 14 days for a full refund.
- A used one cannot — once the profile connects to a network the service has been supplied and the right to withdraw is gone, which you agree to at checkout.
- If an eSIM does not work as described, make a complaint instead. That is a different thing and the 14 days do not apply to it.
- Returns that go through without us having to do anything have a ceiling. Past it, withdraw by e-mail; you lose no right, a person simply handles it.
- Fraud and manifest abuse of the right to withdraw are grounds for us not to refund (Section 8 of the Czech Civil Code). A person decides, a refusal comes in writing with a reason, and you can take it to the Czech Trade Inspection Authority or to court.
- VPN returns go by e-mail, not by a button — write to support@semperonline.com. Cancelling a subscription is not the same as a refund: it stops further renewals and returns nothing for the period already paid for (clause 7).
10. Buying as a business
We sell to businesses as well. If you buy in the course of your business, consumer protection does not apply — specifically:
- no right to withdraw within 14 days under section 9; we will usually still take back an unused eSIM on the same terms, but that is goodwill, not your right,
- no 30-day deadline for settling a complaint, and no alternative dispute resolution through the Czech Trade Inspection Authority,
- liability for defects follows the general business-to-business rules.
You enter your VAT number on the payment screen; with a valid number from another EU member state the reverse charge applies and the document is issued without VAT.
What decides it is a company or VAT number entered on the order: if you give one, we treat the purchase as a business one. If you would rather keep your consumer rights, leave those fields empty — you get an invoice either way.
11. Your account
Your password is yours to look after. If you think someone else has it, change it — that signs out every device.
We may close an account that is abusing the service. Closing it does not cancel eSIMs you have already paid for, nor what we owe you for them.
12. What we are not responsible for
- Coverage, speed and outages on operators' networks.
- Your phone not supporting eSIM, or being carrier-locked.
- Lost data, lost profit, and the cost of working around a problem — another SIM, a hotel phone.
Our liability is limited to the price of whatever the matter concerns — the plan or the VPN access, and for a subscription the price of one period.
Nothing here limits our liability for intentional harm, gross negligence, or personal injury.
13. Disputes
Write to support@semperonline.com first — almost everything ends there. That is also where complaints go; there is nothing to send by post.
If it does not, a consumer may take the dispute to the Czech Trade Inspection Authority (Česká obchodní inspekce), Štěpánská 567/15, 120 00 Prague 2, <https://adr.coi.cz>. Telling you this is required of us by Czech consumer protection law.
We deliberately do not point you at the EU online dispute resolution platform: it closed on 20 July 2025, and with it the duty to link to it. A link to it today is a link to a dead page.
14. Governing law and language
Czech law governs. This does not take away the protection you have under the law of the country where you live, where that protection is stronger.
The Czech version of these terms prevails; this translation is for convenience.
15. Changes
We reserve the right to change these terms at any time — catalogues, currencies, suppliers and laws all move, and the terms have to be able to follow.
A change is not retroactive: the version in force when you completed your order is the one that governs it, and we will send it to you on request. A new version applies to orders placed after its effective date, which is always shown at the top.