How a port actually works in Ireland
Ireland runs gaining-provider-led mobile number portability. You never ask the old network for permission, and there is no UK-style PAC code. You sign up with the new provider, tick keep my number, prove you hold the number (a one-time text to the old SIM), and the new provider sends the request to the old network. The old network checks the details, approves, and the number is re-routed. Your old SIM goes dead, your new SIM comes alive. That is the whole thing.
ComReg’s rules, restated plainly: porting is free, the new provider leads, you can agree the date, the process should not be delayed without reason, and when something goes wrong you should not be without service for more than one working day. Providers must publish a compensation scheme for loss of service or delay during a switch. Those rules sit in ComReg’s Phone and Broadband Switch Guide (2025 edition) and the switching pages on comreg.ie.
The practical timeline is tighter than the rule. The Irish industry process clears single-line consumer ports in a couple of hours during porting hours, which is why Eir, Tesco, Virgin and An Post all print “2 hours” in their own terms. Bill pay takes longer than prepay because the old network checks the account before releasing it. Multi-line accounts take longest.
If you just want the steps, read how to switch mobile provider. This page is for when you want to know why it failed.
What each network asks for when you port in
Every gaining provider needs three things: the number, proof you hold it (SMS code to the old SIM), and enough about the old account to get it released. The difference is how they collect it and how fast they promise delivery. Verified on provider help pages and PDFs in August 2026; 48 and GoMo sites are JS-rendered, so we used their help PDF and community knowledge base.
| Porting to | Radio | Where you request it | What they ask for | How fast they say |
|---|---|---|---|---|
| Three | Three network | three.ie/keep-your-number (four-step form) | SMS code to the old number, SMS code to the new Three number, account type (prepay registered / unregistered, bill pay single / multi), old account number for bill pay | 2–4 hours after the old network approves it, during porting hours |
| Vodafone | Vodafone network | Checkout (“switch your number”) or My Vodafone / 1907 | Old number, old provider, account number for bill pay. Prepay ports are typically the fastest on Vodafone | Typically same day; prepay often inside 2 hours |
| Eir Mobile | Eir network | eir.ie/porting or the eir app | Old number, account type, account number for bill pay, SMS verification | Prepay within 2 business hours (Mon–Fri 9am–7pm); single-line bill pay within 8 business hours; multi-line within 24 hours |
| 48 | Three network | My48 → My Profile → Move Your Number | Old number, SMS security code to the old SIM, account type, old account number for bill pay. Old SIM must still be active | Typically same day; 48 asks for up to 24 hours |
| GoMo | Eir network | Checkout “Keep My Number” or MyGoMo → Move my Number | Old number, SMS verification code, date and time, account type; account number only for bill pay | A few minutes up to 24 hours; multi-line bill pay up to 48 hours |
| Clear Mobile | Vodafone network | Online signup, transfer date chosen at checkout | Old number, old provider, account number | Typically within 24 hours of the chosen date |
| Tesco Mobile | Three network | My Tesco Mobile app → Move My Number, or text PORT to 23424 | Both SIMs to hand, SMS code to the old SIM, account number for bill pay | Up to 2 hours single line, up to 8 hours multi-line. Mon–Fri 8am–6pm, weekends 10am–4pm |
| Sky Mobile | Vodafone network | At SIM activation, before the plan goes live | Old number, old provider, account number, SMS code to the old SIM | Typically minutes to hours after activation |
| Virgin Media | Three network | Porting form after the SIM arrives | Virgin account number from the SIM letter, old provider, old account number (bill pay) or registered / unregistered (prepay), SMS code | Up to 2 hours, Mon–Sat 9am–6pm |
| Lycamobile | Eir network | lycamobile.ie transfer form or 322 | Old number, old provider, account details. Lyca’s help pages are partly UK-templated (they mention a PAC); in Ireland it is still a provider-led port | Lyca quotes up to 2 business days, longer than the big three |
| An Post Mobile | Vodafone network | Activation call / form, 0818 789 789 | Old number, old provider, account type and number | Within 2 hours at an agreed time (An Post terms) |
Three things to notice. First, prepay ports rarely need an account number: you pick “prepay registered” or “prepay unregistered” instead. Registered means the old network has your name and address on file. If you never registered a prepay SIM, say unregistered or the name check will fail. Second, bill pay always needs the account number exactly as printed on the bill; ComReg’s guide calls this the UAN. Third, porting hours matter. A request submitted Saturday night on a network that ports Mon–Fri 9am–7pm (Eir) is not stuck, it is queued. Tesco and Virgin do port at weekends, in shorter windows.
Before you press go
- Keep the old SIM in a phone, active and in credit. The verification text lands on it, and the port pulls from it. An expired prepay SIM or a cancelled account cannot be ported. Prepay expiry rules by network: prepay expiry rules.
- Do not cancel first. A completed port closes the old account for you. Cancelling first hands the number back to the pool and can lose it for good.
- Use up prepay credit. It is lost on port. Three, Tesco and 48 all say so in their own help pages. Three adds that you “may be entitled to a refund”, which means asking care, not an automatic credit note. Paid-for bundles die with the SIM.
- Bill pay: the early termination fee still applies. The port does not cancel your minimum term, it just ends the service. If you are inside a 12- or 24-month term, the old provider bills the remaining months or its exit formula on the final bill. Numbers by network in mobile early termination fees. Clear an outstanding balance first, because some networks reject the port until it is paid.
- Unlock the phone. A network-locked handset will accept the port and then refuse the new SIM. Tesco lists this in its own porting checklist. How to check and what each network charges: unlock your phone.
- Match the name and date of birth. Married name, middle name, Irish-language spelling, “Dublin 4” vs an Eircode. Enter it the way the old account holds it, not the way you would write it today.
- Pick a sensible time. A Tuesday at 10am gets you a port inside the same working window, with a human on the phone if it wobbles. Friday at 5pm does not.
Timeline, step by step
This is a typical single-line consumer port submitted inside porting hours. Bill pay and multi-line accounts stretch the approval step.
| Step | What happens | Typical time | Old SIM | New SIM |
|---|---|---|---|---|
| 1. Request | You submit the port with the new provider and enter the SMS code sent to the old SIM. | Minutes | Working | Temporary number only, or nothing yet |
| 2. Validation | Old network checks name, account type and number. Rejection happens here if anything mismatches. | Minutes to a few hours (prepay fast, bill pay slower) | Working | Temporary number only |
| 3. Cut-over | Routing switches to the new network. The old SIM drops to “no service” or “emergency calls only”. That drop is your signal, not a fault. | Within the 2-hour window most networks quote | Dead | Insert it now, restart the phone |
| 4. Calls live | Outgoing calls work first. Incoming calls follow as other networks update routing. | Minutes after cut-over | Dead | Calls yes |
| 5. SMS live | Texts from people on your old network and some automated senders (banks, 2FA) can lag while routing tables catch up. | Minutes to a few hours; rarely longer | Dead | Calls yes, SMS catching up |
| 6. Data live | Usually immediate once the SIM registers. If not, the new APN has not been pushed: restart, or set it by hand from the provider’s help page. | Immediate to 30 minutes | Dead | Everything |
| 7. Old account closes | Prepay: credit gone. Bill pay: final bill, with any ETF, follows in the next cycle. | Days to weeks for the final bill | Gone | Your number, new network |
GoMo’s own instructions are the cleanest description of step 3: leave the current SIM in, wait until the signal goes, then pop the GoMo SIM in and restart. Virgin says the same thing in different words. Do not swap early.
What can go wrong, and the fix for each
| Symptom | Usual cause | Fix |
|---|---|---|
| Port rejected, “details do not match” | Name, date of birth or address differs from the old account. Common with married names, shortened first names and prepay SIMs registered years ago. | Ring the old network, ask what name and DOB they hold, resubmit the port through the new provider with those exact values. Do not guess twice; some networks lock the request after repeated failures. |
| Port rejected, “invalid account number” | You entered a SIM serial, a phone number or the new provider’s account number instead of the old bill’s account number. Or you picked bill pay for a prepay SIM. | Take the account number off the latest bill or the old provider’s app. For prepay, choose prepay registered / unregistered; no account number is needed. |
| Old SIM already cancelled or expired | You cancelled first, or a prepay SIM passed its inactivity limit and the number was disconnected. | Ring the old network immediately. Numbers are usually held for a period before reissue and can sometimes be reactivated, then ported. There is no guarantee. This is the one failure that can be permanent. |
| Port rejected, outstanding balance | Unpaid bill or a failed direct debit on the old bill-pay account. | Pay it, get a confirmation, resubmit. The ETF itself does not block a port, an overdue balance can. |
| No verification text arriving | Old SIM not in a phone, old SIM out of credit on a network that needs credit to receive, or phone on Wi-Fi calling with no signal. | Put the old SIM in any unlocked handset with signal, top up €5 if it is prepay, request the code again. |
| Nothing happened for 24 hours | Submitted outside porting hours, or a multi-line / business account that needs manual approval. | Wait one full porting window. Then ask the new provider for the port reference and the old network’s response. Business accounts need the account holder, not the user, to authorise. |
| Calls work, texts do not | Partial port: voice routing updated, SMS routing not yet. Reported on Sky and Lyca ports on boards.ie and Sky’s help forum. | Give it a few hours. If it persists past a working day, the new provider must raise it with the other networks to refresh routing. Insist on a ticket. |
| WhatsApp, bank or app still shows the old network | Apps cache the carrier name. Banks and 2FA senders use SMS gateways that refresh routing on their own schedule. | Restart the phone, toggle flight mode, re-verify WhatsApp if prompted (it keeps your chats, the number has not changed). Give bank SMS codes up to a day; use the bank app’s in-app approval meanwhile. |
| Number ported, but phone says “SIM not supported” | Handset is locked to the old network. | Unlock with the old network; the port itself is fine. See unlock your phone. |
| Landline refused | You tried to move a geographic (01, 021…) number to a SIM. | Not possible. Geographic numbers port between fixed and VoIP providers only; 08x numbers port between mobile providers only. |
Same-radio and internal ports
A port moves the number between retailers, not between masts. The host radio is a separate question; see MVNO explained for who rides what.
- 48 → Tesco or Virgin stays on Three radio. Coverage does not change, the port is still a full port between two retailers. Same for Clear → An Post or Sky (Vodafone radio) and Eir → GoMo or Lycamobile.
- 48 → GoMo, Tesco → Clear, or 48 → Sky or Lycamobile changes radio. The port is no slower, but coverage at home can change the day the SIM goes live. Test the new radio on a second SIM before you port if indoor signal is marginal; best mobile network in Ireland covers the masts.
- Three ↔ 48 is an internal move inside the same group. It still runs as a normal port request (three.ie/keep-your-number one way, My48 → Move Your Number the other) and it is not instant. 48’s own community confirms you port the number back to Three to keep it if you move up. The money side is on Three vs 48.
- Eir ↔ GoMo works the same way: two retailers, one radio, a real port. GoMo says a few minutes to 24 hours. Lycamobile has been on the same Eir radio since late 2025, so Eir ↔ Lyca is also a same-masts port.
- Sky SIM → Sky eSIM is the odd one. Sky cannot port Sky to Sky; the fix is to convert the existing SIM to an eSIM in the Sky app, not to buy a second Sky SIM and try to port between them.
eSIM ports: when to scan the QR
On the plans we list, eSIM is available from Vodafone, Three, Eir, GoMo, Sky and Lycamobile. 48, Clear, Tesco, Virgin and An Post still post plastic. Who supports what, with phone compatibility, is on eSIM in Ireland. This section is only about timing.
With plastic, the order is obvious: old SIM dies, you swap cards. With eSIM there is no card, so people install the eSIM profile early and then watch both lines fight. The safe sequence:
- Install the new eSIM profile when the provider sends it (QR or in-app). Label it “new”. Leave the old SIM as the default line for calls, texts and data.
- Submit the port. The verification text still goes to the old line, which is why the old SIM must stay in the phone or the old eSIM must stay enabled.
- When the old line drops to no service, switch the default line to the new eSIM and restart. Only then delete the old profile.
GoMo (app-only), Eir (eir app) and Sky (Sky app) all issue the eSIM before the port completes, so the number arrives on an already-installed profile. Vodafone and Three issue eSIM on port-in as well. If a provider emails a QR with a time limit on it, install it inside the limit even if the port is scheduled for later; the profile waits for the number.
Who to call when it is stuck
- The new provider, first and always. They own the port. Ask for the port reference, the submitted details, and the rejection code or the old network’s response. Most “stuck” ports are a rejection the customer was never told about.
- The old provider, for one thing only: what name, DOB, account number and account type they hold. Do not ask them to cancel, release or “free up” the number. That is how numbers get lost.
- Log a formal complaint with the new provider if a working day passes without service. ComReg’s rules entitle you to compensation for loss of service or delay during a switch, and the provider must publish its scheme.
- ComReg Consumer Care if the complaint goes nowhere: (01) 804 9668, Monday to Friday 8am–8pm, Saturday 9am–1pm, or [email protected], or text COMREG to 51500 for a call back. ComReg will generally want to see that you have complained to the provider first.
Once the number is safely across, pick the plan on cash, not on how painless the port was: 48 vs GoMo vs Clear for the €12.99 floor, or the full best mobile in Ireland list.
