The best folding treadmill for home use in the UK, if folded size matters, is the MERACH MR-T12B2: it is the only model here with a published folded size, 65 x 70 x 125cm. Reebok's GT40z and NordicTrack's T Series 8 both fold but publish no folded dimensions. Ranking follows published specification, not testing.
This site does not test products. Figures come from the makers' own pages and data sheets, and anything a maker does not publish is marked "Not published".
What does "folding" mean on a treadmill?
A folding treadmill lifts the running deck upwards so the machine takes up less floor area. That helps in a flat or spare room, but the machine still needs its full footprint when it is in use, plus clear space behind the belt. Three details decide how useful a fold is in a small home.
- Folded dimensions. Without a stated folded height, depth and width you cannot check a cupboard, alcove or wall space. Some makers do not publish them.
- Fold mechanism. MERACH describes hydraulic folding that it says takes 5 seconds and can be done with one hand, and Reebok describes a soft drop hydraulic fold. NordicTrack's data sheet lists the T Series 8 as foldable without naming the mechanism.
- Moving it. MERACH and Reebok both list transport wheels. Check the weight of the machine against who will be moving it; MERACH and Reebok give no net weight on the pages used here, and the NordicTrack sheet gives only a package weight of 113.3kg.
Specification comparison
| Model | Fold | Folded size | Set-up size | Top speed | Max user weight | Indicative price |
|---|---|---|---|---|---|---|
| MERACH MR-T12B2 | Hydraulic | 65 x 70 x 125cm | Not published | 12km/h | 136kg | around £329.99 (checked Oct 2026) |
| Reebok GT40z | Soft drop hydraulic | Not published | 168 x 77 x 134cm | 18km/h | 110kg | around £549 (checked Oct 2026) |
| NordicTrack T Series 8 | Foldable, mechanism not named | Not published | Not published | Maker figures conflict (12 and 20km/h) | 147kg | No price checked |
Full details are in the MERACH MR-T12B2 review and the Reebok GT40z review.
Which folding treadmill publishes its folded size?
Of the models compared here, only the MERACH MR-T12B2 publishes its folded size, 65 x 70 x 125cm, with a footprint the maker gives as 4.84 sq ft. Multiplying the stated 65cm by 70cm gives about 0.45 square metres of floor, which matches that figure (reasoning from the stated numbers). MERACH also says the machine is 90% pre-assembled and covered by a 24-month warranty.
Its limits are the 12km/h top speed and the 108 x 41.9cm belt, which suit walking and jogging more than fast running. The page lists no set-up size, so the room needed in use cannot be worked out from MERACH's figures. Ask the retailer before ordering.
How does the Reebok GT40z fold?
Reebok describes a soft drop hydraulic folding mechanism that lets you fold the running deck when it is not in use, and lists transport wheels. It does not publish folded dimensions. Reebok lists the GT40z at 1 to 18km/h with 12 electronic incline levels and a 130 x 45cm running area, and its set-up size is 168cm long, 77cm wide and 134cm high.
Because the folded size is not given, measure the space you intend to use and ask the retailer or Reebok for the folded dimensions first. The maximum user weight is 110kg (17.3 stone), and the page states no warranty.
What is the maximum user weight on these folding treadmills?
The makers list 136kg for the MERACH MR-T12B2, 110kg for the Reebok GT40z and 147kg for the NordicTrack T Series 8. Check the figure against the heaviest user before buying. The NordicTrack data sheet adds a disclaimer that the machine is not for users over 148kg.
The NordicTrack lists a 152 x 51cm belt, the largest of the three, but gives no folded size, and its own figures for top speed disagree, so confirm both with NordicTrack or the retailer. NordicTrack's UK treadmill page lists a 10-year motor warranty and a lifetime frame warranty for the range, subject to registration.
Do I need space when a folding treadmill is in use?
Yes. Folding only reduces storage space. Reebok, for example, lists a set-up size of 168 x 77 x 134cm, which is about 1.29 square metres of floor before clearance, and you also need clear space around the machine, so measure the room as well as the storage spot. The maker's manual is the place to find the required clearance behind the belt.
Delivery, assembly and returns
MERACH states free shipping and a 3 to 7 business day transit time, with processing within 48 business hours on top, and 30-day returns for new, unused products. Reebok's page says shipping is calculated at checkout and listed the GT40z as backordered when it was opened for this guide, with no delivery times. The NordicTrack data sheet gives a package weight of 113.3kg, which is worth planning for when arranging a delivery team and a route into the building.
GOV.UK says customers can cancel an online order up to 14 days after delivery without giving a reason. A retailer's own terms may differ on assembled machines, so read the returns policy before opening the box.
Why are some treadmills not compared in this guide?
The Where to buy block also lists the Horizon Fitness TR3.0, BodyTrain 7001 and Bowflex BXT8Ji. Their specifications could not be confirmed from a maker page or manual that was open at the time of writing, so this guide quotes no figures for them. Folded size in particular should be read from the maker's manual, not assumed.
What else do the maker pages list about each machine?
Beyond the fold, the three pages describe different control and comfort features, which matter if the machine will be used by more than one person.
- MERACH MR-T12B2: an LED display showing time, calories, speed, distance and heart rate, a remote control, a safety handle and a heart rate monitor, plus the free Merach app with Kinomap, Zwift, Apple Health and Google Fit listed. The page does not list a conventional safety key.
- Reebok GT40z: a 5-inch LCD, 36 pre-set, 3 user-defined and 3 target programmes, quick speed and incline keys on the hand rests, hand pulse sensors, a tablet stand and floor level adjustment for a stable running platform. The page does not mention a safety key.
- NordicTrack T Series 8: a 7-inch display, SelectFlex cushioning with soft or firm settings, a built-in fan and a USB-C port per the data sheet. NordicTrack's UK page says a paid iFIT Pro membership is required to access content and features, listed at £34 a month.
None of these lists is a recommendation. Check the manual for how the machine stops if the user steps off, because that is a safety feature and the pages differ in what they say.
What to check before buying
- Folded height, width and depth, and whether the maker states them.
- Whether the room has the full set-up footprint plus clear space behind the belt when the machine is in use.
- Floor loading and noise if the machine will sit upstairs; see the home gym ventilation and noise guide.
- Where the machine will live between sessions. The storage ideas guide covers stowing equipment in small homes.
- The maker's manual for safe folding and unfolding, and the home gym safety notes. A GP can advise first if you have health concerns.
Who should skip a folding treadmill?
If you will use the machine daily and never need the floor back, a fixed machine with a larger belt may suit better; the general home treadmill guide compares the same models without the fold requirement. If low-impact cardio in a very small space is the aim, read treadmill vs exercise bike.
Fast runners should also skip the MERACH, whose published ceiling is 12km/h, and anyone who needs a published folded size should skip the Reebok and NordicTrack until the maker supplies one.
Price context
At the last check the MERACH was around £329.99 and the Reebok around £549 (both checked Oct 2026). Prices move, so confirm the current figure on the retailer's page. No price was checked for the NordicTrack T Series 8. For the activity target a treadmill helps with, the NHS recommends adults aged 19 to 64 do at least 150 minutes of moderate or 75 minutes of vigorous activity a week.
