South Mimms services
Welcome Break · J1 (M25 J23) · off the junction roundabout, all directions · open 24 hours
A1(M) Hertfordshire section · National Highways
Mobile tyre fitting
Mobile tyre fitting
on the A1(M).
The A1(M) through Hertfordshire is one of the motorways nearest our Brent Cross base, after the M1, but our fitters stay off its hard shoulder and out of the Hatfield Tunnel. If the car is under control, leave at the next exit or services. A car that cannot be driven is a 999 or National Highways 0300 123 5000 matter first, then recovery, then us.
★★★★★5.0 on Google from 151 reviews·Arrival time confirmed before we set off
About the A1(M)
Where breakdowns happen
Where breakdowns happen
and where we can meet you.
From the M25 at South Mimms to Baldock, the A1(M) is the Hertfordshire commuter road, feeding Potters Bar, Hatfield, Welwyn Garden City, Stevenage and Letchworth into London. The Hatfield Tunnel between J3 and J4 passes under the Galleria, where stopping is prohibited. Services sit at both ends, South Mimms at M25 J23 and Baldock at J10, and every junction between lands you in a town. The climb out of Welwyn past Knebworth is where soft tyres give up.
- No hard shoulder: Hatfield Tunnel between J3 and J4
- No stopping: Hatfield Tunnel between J3 and J4
- Road operator: National Highways (0300 123 5000)
Before anything else
Get off the live carriageway
If you can still control the car safely, leave at the next junction or pull into a services. If not, use the hard shoulder or an emergency area rather than a running lane, but never as a place to wait for a fitter: nobody can change a wheel there.
If you cannot move
Put your hazards on. If it is safe, get everyone out on the passenger side and behind the barrier; if not, stay in with seatbelts on. Call 999 if you are in a live lane or in danger. Otherwise call the road operator (details below) and get moved to a place of safety. On a smart motorway use an emergency area and the orange SOS phone, and do not rejoin until the signals are set.
Then call us
Once you are somewhere a van can park beside you, call 07473 720871 with the road, the direction, the nearest junction or marker post and the tyre size. We confirm the price and a realistic time before we set off.
Junction by junction
Where on the A1(M) we can meet you.
The usual arrival band from our Brent Cross base; we confirm a real time when you call.
| Junction | Serves | Nearest safe stop | Typical arrival |
|---|---|---|---|
| J1 | M25 J23, A1 for London, South Mimms services | South Mimms services on the roundabout | Usually under an hour |
| J2 | A1001 Welham Green (northbound exit and southbound entry only) | Welham Green village roads off the A1001 | Usually under an hour |
| J3 | A414 St Albans and Hertford, A1001 Hatfield, the Galleria | Hatfield side roads, or the Galleria car park where the operator allows it; with a failing tyre, leave here rather than enter the tunnel | Typically 60 to 90 minutes |
| J4 | A414 Hertford, A6129 Stanborough and Welwyn Garden City, A1001 Hatfield (southbound) | Welwyn Garden City via Stanborough, or Hatfield side roads | Typically 60 to 90 minutes |
| J5 | Northbound entry slip only, from the A1000 at Welwyn; no exit in either direction | No exit here: carry on to J6 while the car is under control | Typically 60 to 90 minutes |
| J6 | A1000 Welwyn, Welwyn Garden City north, Digswell | Welwyn village or Welwyn Garden City town centre car parks | Typically 60 to 90 minutes |
| J7 | A602 Stevenage south, Knebworth, Ware and Hertford | Knebworth village or the retail parks on the southern edge of Stevenage | Typically 60 to 90 minutes |
| J8 | A602 Hitchin, Stevenage north, Stevenage station | Stevenage town centre car parks or the station car park | Around 1.5 to 2 hours |
| J9 | A505 Letchworth Garden City and Baldock (via the A6141 Letchworth Gate) | Letchworth town centre car parks or the A505 retail units | Around 1.5 to 2 hours |
| J10 | A507 Baldock, Stotfold, Shefford, Baldock services; the motorway becomes the A1 north of here | Baldock services on the roundabout, or Baldock town | Around 1.5 to 2 hours |
Services on the A1(M)
Baldock services
Extra · J10 · off the junction roundabout, both directions · open 24 hours
Off the road
What can we do once you are off the A1(M)?
Parked at South Mimms, in a Potters Bar or Stevenage station car park, if permitted, or at Baldock services, we fit, repair or free a locking nut.
Puncture repair once you are off the A1(M)
A slow puncture from the Hatfield school run or the Stevenage retail parks can be dealt with off the A1(M), on the same day when the schedule has space. Between Potters Bar and Welwyn, take the next exit and park in town. A small central hole is patch-plugged under BS AU 159.
How a mobile puncture repair is done →Burst and damaged tyre replacement on the A1(M)
The northbound climb out of Welwyn towards Knebworth is where low tyres tend to burst on the A1(M). Hold the wheel, let the car slow itself and take J6 or J7 if it still steers. If not, pull onto the hard shoulder, leave by the left doors and wait behind the barrier. Never stop in the Hatfield Tunnel unless forced to.
What to do after a burst tyre →Locking wheel nut removal at the services
South Mimms is where a Hertfordshire driver can end up with the spare on the ground and a locking nut that will not shift. Our removal tools take the nut off without damaging the wheel, whether the key is lost, rounded or seized, and the same goes for Baldock services and any station car park between Potters Bar and Letchworth.
How locking wheel nuts are removed →24 hour cover for the A1(M)
Late trains into Stevenage and Hatfield and early starts from Letchworth put people on the A1(M) at every hour, and this is one of the motorways where an overnight callout from Brent Cross is practical. South Mimms and Baldock are open all night, and the station car parks at Potters Bar, where the operator allows it, Hatfield and Stevenage are level.
How our 24 hour tyre service works →Every tyre service on the A1(M)
Motorway advice follows the Highway Code (motorway rules 253 to 273 and breakdown rules 274 to 287) and National Highways breakdown guidance; repairs follow BS AU 159, the British Standard for tyre repairs.
Real situations
Stopped on the A1(M): what happens next.
J3 Hatfield: pressure warning just before the tunnel
The tyre light comes on approaching the Hatfield Tunnel northbound. While the car still steers, take J3 and park in a Hatfield side road; never stop inside the tunnel unless the car has failed.
J6 Welwyn: tyre bursts on the northbound climb to Knebworth
A tyre low for weeks gives up climbing out of Welwyn. Keep both hands firm and stay off the brake until the car slows; if it still steers, take J7 for Knebworth and a side road.
South Mimms J1: locking nut seized solid
You pull into South Mimms off the J1 roundabout with a puncture, get the wheel brace on and the locking nut refuses to turn. Use the car parking and the nut is freed with the alloy undamaged.
A1(M) FAQs
Questions drivers on the A1(M) ask.
Can I stop in the Hatfield Tunnel if my tyre goes?
Only if the car cannot continue. The tunnel has no hard shoulder and stopping is prohibited, so while it steers, keep going and leave at J4 for a Welwyn Garden City or Hatfield side road. If forced to stop inside, get out and use the emergency phones.
Which services are on the A1(M) in Hertfordshire?
Two. South Mimms at J1, shared with M25 J23, and Baldock at J10 at the northern end of the motorway section. Nothing sits between them, so for Hatfield, Welwyn and Stevenage drivers the exits at J3, J4, J6, J7 and J8 lead to the stopping points.
My tyre is losing pressure northbound near Welwyn. Where should I head?
J6 for Welwyn and Welwyn Garden City is usually nearest, with plenty of car parks. If you have passed it, J7 puts you at Knebworth or the southern edge of Stevenage. Do not try to reach Baldock on a tyre that is visibly going down.
Is the A1(M) closer to you than the Midlands roads?
Considerably. South Mimms is one of the closest services to NW2, though London Gateway on the M1 is nearer, and Baldock sits at the far end. You get an honest arrival estimate when you ring, not a guarantee, once the car is somewhere we can work.
Will you come to Stevenage station car park?
The station car park at J8, if permitted, is a good place to meet: level and close to the motorway. It is pay-and-display so allow for that. If the multi-storey is full, the retail parks along the A602 near the junction are a fair alternative.
I stopped on the hard shoulder near Potters Bar. Can you fit the tyre there?
No, and please do not wait in the car. Get out on the left, stand behind the barrier and call 999 if you are in danger. Your breakdown provider then recovers the car to Potters Bar or South Mimms, where we fit the tyre.
Does the A1(M) have any all-lane running without a hard shoulder?
Apart from the Hatfield Tunnel, no. The Hertfordshire section is a conventional motorway with a hard shoulder throughout, for emergency stopping only. There are no emergency areas to look for; simply get behind the barrier and call for recovery if the car will not move.
Can you meet me at South Mimms if I have come off the M25?
South Mimms services sits on the roundabout shared by A1(M) J1 and M25 J23, so it does not matter which motorway you arrived from. Park in the car area, away from the lorry park and the fuel forecourt, and tell us your registration.
Is a same day fitting at my house in Potters Bar or Hatfield possible?
Potters Bar and Hatfield sit near Brent Cross, so a same-day driveway fitting may be possible if the diary has room and the size is on board. Tell us the road off the A1000 in Potters Bar or the side of the Galleria in Hatfield.
What sets the price for a tyre on the A1(M) at Stevenage?
The size and the tyre you choose set most of it, and the run from NW2 up to Stevenage at J8 is built in. One figure is put to you over the phone before the van moves, covering tyre, fitting and callout.
Google reviews
Recent Google reviews.
Rated 5.0 from 151 Google reviews.
★★★★★
"Good and fast service."
BWBaruch WiesenbergGoogle review
★★★★★
"From start to finish, Hiwad was incredibly professional and helpful."
KMKian MGoogle review
★★★★★
"Great service, fixed my punctured tyre quickly and the best prices for mobile repairs."
AAmirGoogle review
Along the A1(M)
Which towns along the A1(M) do we cover?
Roads it meets
Guides
What to do after a motorway breakdown →Tyre breakdown on the M25 →What to do in a tyre blowout →Tyre blowout: causes and prevention →Can a puncture be repaired? →Slow puncture: causes and fixes →
Written and checked by Hiwad Yarkhil, founder of Rescue Tyres LTD, Unit 9 Adrian Avenue, Brent Cross, London NW2 1LX. Updated 2026-10-08.
A1(M) · 24 hours
Off the road and waiting? Call now.
Hatfield, Welwyn, Stevenage or Baldock services: park the car off the A1(M) and the tyre comes to you.