Run-flat tyres have reinforced construction that lets them carry the car's weight with no air inside, so you can keep driving after a puncture to reach somewhere safe. The RAC says most manufacturers recommend not exceeding 50mph and 50 miles after a puncture (RAC), while TyreSafe points out that recommendations vary between makers and that drivers should check the car handbook for the distance and speed allowed (TyreSafe).
Most searches about run-flats come down to four practical questions: how to tell whether your car has them, how far you can drive on one, whether a punctured one can be repaired, and whether you can swap to normal tyres. This guide answers each one, with a marking-by-brand table so you can check your own sidewalls.
How to tell if a tyre is run-flat
The quickest way to tell if a tyre is run-flat is the sidewall: look for a run-flat marking next to the size or the brand name. If you can't find one, work through the other checks below.
- Read the sidewall. The RAC advises looking for "terms like Run-Flat, SSR (Self-Supporting Run-flat), RFT (Run-Flat Technology), ROF, or similar abbreviations". The AA adds the letters "RF" and a symbol of a flat tyre with an arrow pointing upward. The table below lists the common codes.
- Check the handbook or the tyre specification for your model. It will say whether the car was supplied on run-flats.
- Look in the boot. A car on run-flats often has no spare wheel. That's only a clue, though: many cars without a spare come on standard tyres with a sealant kit instead.
- Feel the sidewall. The AA notes that run-flats "typically have a thicker and stiffer sidewall than regular tyres", although that's hard to judge without a standard tyre to compare.
Still unsure? Send a photo of the sidewall to a fitter. Our guide to how to read a tyre size shows where each marking sits.
Run-flat tyre markings by brand
Each tyre maker uses its own name for run-flat technology, so the same kind of tyre can carry several different codes. These are the markings confirmed by the tyre makers and motoring organisations listed in the sources:
| Sidewall marking | What it stands for | Used by | Source |
|---|---|---|---|
| RFT | Run-Flat Technology | Used by several makers | RAC |
| SSR | Self-Supporting Run-flat | Continental | RAC, Continental |
| ROF or RunOnFlat | RunOnFlat | Goodyear | Goodyear |
| EMT | Extended Mobility Technology (Goodyear, older tyres); Extended Mobility Tyre (Michelin) | Goodyear, Michelin | Goodyear, Michelin |
| ZP | Zero Pressure | Michelin | Michelin |
| RF or Run-Flat, or a flat-tyre symbol with an upward arrow | Run-flat | General markings | AA |
A star is not a run-flat marking. Goodyear lists the star as the BMW Group's original equipment marking, showing a tyre approved for BMW vehicles (Goodyear). Many BMW and MINI models come on run-flats, so you'll often see a star and a run-flat code on the same tyre, but the star alone doesn't tell you the tyre is a run-flat.
Other makers use their own codes and product names. The RAC notes, for example, that Bridgestone brands one of its products DriveGuard. If a tyre carries a code not listed here, the maker's website or a fitter can confirm what it is.
How far and how fast can you drive on a run-flat?
Typically up to 50 miles at up to 50mph after total pressure loss, but the figure varies by tyre and car, so the handbook has the final word. Here's what the makers and motoring organisations say:
| Source | Distance and speed after a puncture |
|---|---|
| Goodyear | "At least 50 miles at up to 50mph" on a punctured RunOnFlat tyre |
| Michelin | Up to 80km at no more than 80km/h, varying with load, temperature and road conditions |
| RAC | Most manufacturers recommend not exceeding 50mph and 50 miles |
| TyreSafe | Recommendations differ between makers; check the car handbook |
Treat those numbers as a limit, not a target. Drive gently, avoid sharp cornering and heavy braking, and head for the nearest safe place to stop. Load matters: a car full of passengers and luggage puts more strain on a deflated tyre than a driver alone. On a motorway, if the car is handling normally, leave at the next junction or services rather than stopping on the hard shoulder; if not, use the hard shoulder or an emergency area and get behind the barrier, and call 999 if you're ever in danger.
How run-flat tyres work, and why they need TPMS
A run-flat's reinforced structure carries the weight of the car when the air pressure that would normally do that job has gone. Michelin describes "reinforced sidewalls that help support the car's weight", and Goodyear says "highly resilient rubber inserts support the weight of the car even when the air pressure... is gone".
Three things follow from that design:
- You may not feel the puncture. Because the tyre doesn't collapse, the car can feel almost normal. Goodyear states that "the vehicle must be fitted with a Tyre Pressure Monitoring System (TPMS) in order to alert the driver in the event of a puncture". The RAC adds that a working TPMS "will be checked at your annual MOT". For cars first used on or after 1 January 2012, a malfunctioning TPMS is a major MOT defect (MOT inspection manual). See TPMS warning light explained.
- The wheel and car have to suit them. Michelin says run-flats can only be mounted on rims with double humps and need approval for your vehicle model.
- You still need to check pressures. Goodyear advises monthly manual checks even with TPMS, because the system doesn't account for added load and readings can be inaccurate.
Can a run-flat tyre be repaired?
Sometimes, but it depends on the tyre maker, and a run-flat that has been driven any real distance while deflated is usually a replacement. The sources don't all agree, which is why the answer varies from tyre to tyre:
- TyreSafe: "For repairs to self-supporting run flat tyres, consult the relevant tyre manufacturer" (TyreSafe). It also warns that driving on a punctured or deflated run-flat "can weaken and permanently damage it, making the tyre both unsuitable and unsafe to repair" (TyreSafe).
- Michelin: its run-flats "can be repaired only once by a professional under the same conditions" as standard tyres, though some may be marked as non-repairable.
- Goodyear: some of its run-flats can be repaired by qualified professionals, but not every variant.
- RAC: in most cases no, because the reinforced sidewalls and specialised construction make a safe repair extremely difficult.
Where a repair is allowed, the normal repair rules still apply. Under BS AU 159 the damage has to be in the central repair zone of the tread and no more than 6mm across (BTMA), and the tyre has to come off the wheel for an internal inspection. In practice: if the warning light came on and you stopped quickly, it's worth asking. If you've driven on it for miles, plan for a new tyre. Our guide to whether a puncture can be repaired covers the standard, and nail in your tyre has a repair decision table.
Can you replace run-flats with normal tyres?
Yes, you can fit standard tyres to a car that came on run-flats, as long as you change all four and have a plan for the next puncture. Before you switch, think through:
- Your puncture plan. A car designed for run-flats may have no spare, jack or sealant kit. Decide whether you'll carry a space-saver, a repair kit or rely on a mobile fitter. See spare wheel vs repair kit.
- All four tyres the same type. The RAC says "it is not recommend to mix run flats with regular tyres" because it affects handling. The MOT manual allows run-flat and conventional tyres on the same axle, "although this is not recommended" (MOT inspection manual).
- The same specification. Continental says replacement tyres should have "the same size, load index, and speed rating specification as specified by the vehicle or tyre manufacturer" (Continental).
- The warning system. TPMS stays part of the car whichever tyres you fit, so a sensor fault still needs fixing.
- Your paperwork. It's sensible to check with your insurer, and a leased car may have to be returned on the tyre type it was supplied with.
Going the other way, from standard tyres to run-flats, isn't a simple swap. Michelin's point about approved rims and vehicle approval applies, so check with the car maker first.
Run-flat vs standard tyres: side by side
Run-flats trade some comfort and repairability for the ability to keep going after a puncture. Here's how the two compare on the points covered above:
| Run-flat | Standard tyre | |
|---|---|---|
| After a puncture | Can be driven gently for a limited distance, typically up to 50 miles at up to 50mph | Stop somewhere safe; fit the spare, use a sealant kit or call a fitter |
| Spare wheel | Often none | Spare or repair kit usually supplied |
| Sidewall | Thicker and stiffer | More flexible |
| Repairable? | Depends on the tyre maker and whether it was driven deflated | Often, within BS AU 159 limits |
| TPMS | Required, to warn you of pressure loss | Fitted to many cars, but not what makes the tyre work |
| Mixing with the other type | Not recommended; keep all four the same type | |
If your car came on run-flats, the car was designed around them, and staying with them keeps its puncture plan intact. If it came on standard tyres, switching to run-flats needs the car maker's approval.
Punctured a run-flat? We come to you
Don't push past the limits, and get the tyre checked as soon as you've stopped somewhere safe. Rescue Tyres supplies and fits run-flat tyres as a fully mobile service from our one base at Brent Cross, NW2, at your home, at work or at a safe place off the road. If you are further out, call and we will tell you whether we can take the job. If the tyre can be repaired under the maker's policy and BS AU 159, we repair it. If not, we source a replacement in the right size and specification for your car.
- Price confirmed on the call before any work
- A realistic arrival time agreed on the call
- Evenings, nights, weekends and bank holidays when the diary allows, at the same price as a weekday job
Call or WhatsApp 07473 720871 with a photo of the sidewall.
Sources
- RAC, A guide to run-flat tyres
- Goodyear, What are RunOnFlat tyres?
- Goodyear, What do the OE markings mean?
- Michelin, What are runflat tyres?
- The AA, Run-flat tyres
- TyreSafe, Tyre FAQs
- TyreSafe, Punctures and puncture repairs
- TyreSafe, Tyre repair and spares
- Continental, Tyre markings
- Continental, Tyre size
- GOV.UK, MOT inspection manual, section 5
- British Tyre Manufacturers' Association, BS AU 159 guidance for tyre industry professionals
