Tech Specs


Build Quality


Treadmill Review

Last Updated: April 29, 2024

The Nautilus T618 treadmill is clearly the best among the Nautilus treadmills. It has a strong motor and a better weight capacity than any offered in the other two Nautilus treadmills. However, it does not make it into our best treadmills for under $1,500 as it fell short of the excellent features we have seen in competitor treadmills in this price range.


The price of the T618 is $1,299.

The T618 Is Built For Users who:

  • Need a high weight capacity treadmill - The T618 can accommodate a user who weighs up to 350 lbs.
  • Enjoy using fitness apps - By syncing RunSocial with the T618, you can access 19 different location and 27 routes, virtually running alongside people around the world. You can also sync with Nautilus Trainer™ 2 to track your workout metrics.
  • Want accurate heart rate tracking - Heart rate monitoring chest straps have been proven to be the most accurate way to track your heart rate during a workout. A wireless chest strap is included in the purchase of the T618.

Why The T618 earned 3.9 stars

The Nautilus T618 treadmill is a good, quality treadmill with many commendable features with a few flaws that lost it points.

  • Good-sized motor - Equipped with a 3.5 CHP motor, the T618 ranks well with two of our best treadmills under $1,500 but is still outdone by the Commercial 1750.
  • Restricted warranty length - A major detraction for the T618 is the short warranty length it comes with. You only receive 15 years on the frame and motor, 5 years for the parts and electronics, and 2 years labor. While the parts, electronics, and labor are fairly standard lengths, the frame and motor warranties are not.
  • Slightly undersized belt - The best treadmills in this price range have belts measuring 22” wide by 60” long, while the T618 measures 20” wide by 60”.

Whether these flaws are a deal-breaker for you will depend on your personal preferences. But overall, most consumers would prefer the best a price range can offer, and Treadmill Reviews cannot say that the T618 is one of the best.

Main Specs - 8/10

Specs “Quick Review”:
  • Motor Size: 3.5 CHP
  • Running Area: 20” W x 60” L
  • Weight Capacity: 350 lbs
  • Folding: Yes
  • Footprint In Use (W, L, H): 35.2” x 72.2” x 57.6”
  • Incline Range: 0% to 15%
  • Max Speed: 12 MPH
  • Treadmill Best For: Walkers, Joggers, Runner
  • Electrical Requirements: 120 volts

Motor Size - The motor in this treadmill is a good sized 3.5 CHP motor. It is powerful enough to easily transition you between the various inclines and speeds. There is a noticeable hum as it runs, but it is fairly easy to ignore as the sound is very even.

Running Area - The running area on this treadmill measures 20” wide and 60” long. This makes the T618 a bit undersized when compared to the best in its price range.

Weight Capacity - This is one of the higher weight capacity treadmills in this price range as the T618 can hold a user weighing 350 lbs. With many only able to hold 300 lbs, this is a significant improvement. The T618 is outdone by the SOLE F80 and its ability to accommodate a user weighing 375 lbs.  

Folding  - The T618 can fold up with little effort on your part as there is a hydraulic system to assist in the folding and lowering process. The handle to lower the deck is easily accessible, much like SOLE treadmills.  

Space / Footprint - Measuring 35.2” wide, 72.2” long, and 57.6” tall, the T618 has fairly standard dimensions for a treadmill in this price range, though it is a bit slimmer than some you may come across. If you are tight on space, this can be a useful feature.   

Max Speed - The treadmill’s max speed is 12 MPH, which is standard on most treadmills at this price range and higher.

Incline - This treadmill has an incline range of 0% up to 15%, which is common among the better treadmills in this price range.

Features - 7/10

Features “Quick Review”
    • Display: Backlit LCD
    • PreInstalled Workout Apps: 26
    • Speakers: Yes
    • Fans: Yes
    • Heart Rate Monitoring: wireless chest strap, hand grips
    • USB port: Yes
    • Audio Jack: Yes
    • Water bottle cubbies: Yes
    • Device holder: Yes

Workout Apps - There are 26 onboard workout programs on the T618, which can be underwhelming when you compare it to the similarly priced ProForm Pro 2000 with its 32 onboard programs. The programs offered on the T618 include heart rate training, interval workouts, and weight management programs.

Display - There are actually 3 different backlit LCD screens on the T618 so you can always view your workout metrics. You can also use the display to indicate which of the 4 profile users you are when using the T618.

Speakers - On either side of the top of the T618, there are two small speakers mounted. Their sound quality is good and remains decent at the higher volume levels. The is some sound degradation at the last couple high volume levels.

Fans - There is one small fan located just below the main LCD screen. No matter the speed, it does not put out that much of a breeze.

Heart Rate Monitoring - Along with the less accurate heart rate monitoring hand grips, the T618 comes with a wireless chest strap. You can adjust this chest strap to fit you and receive accurate feedback on your heart rate.

Other Tech Features
  • RunSocial app sync available
  • Nautilus Trainer™ 2 app sync available
  • Speed and incline adjustment buttons on treadmill arms

Build Quality - 7/10

T618 Review: Build Quality

  • Warranties - 15 years frame and motor, 5 years parts and electronics, 2 years labor
  • Belt - 2-ply
  • Roller Size - 2.75”
  • Cushioning - Rebound™ Cushioning
  • Customer Support - Phone, email
  • Return Policy - 6-week window

We are not fans of the frame and motor warranty length on the T618. The parts, labor, and electronics warranty is a more standard length but the 15-year frame and motor warranties are not. This makes us concerned about the probable lifespan of the T618.

There is a generous 6-week return window on the T618. Most treadmill manufacturers offer only 30-day return windows. Your money back guarantee will not include the money you paid for shipping and handling or any assembly fees if you paid for assembly.

Bottom Line Review Of The Nautilus T618 Treadmill

We liked testing the T618 as it is a good treadmill, constructed with quality parts. But when compared against treadmills in the same price range, the flaws of the T618 became apparent.

  • NordicTrack Commercial 1750 has a 7” web-enabled touchscreen and a motor which is a powerful 3.8 CHP motor. The T618 only has a backlit LCD screens and a 3.5 CHP motor.
  • ProForm Pro 2000 has 32 workout programs built into it and a belt which measures 22” wide by 60” long. The T618 only has 26 built-in workout programs and a belt which measures 20” wide and 60” long.
  • SOLE F80 can accommodate a user weighing 375 lbs and has a lifetime warranty on its frame and motor. The T618 only can accommodate a 350 lbs user and has a 15-year warranty on the frame and motor.
You may want to check out these treadmills before you settle on purchasing the Nautilus T618.

Best Place To Buy The Nautilus T618 Treadmill

If you would still like to purchase the T618, we would recommend that you choose to work with Nautilus directly on your treadmill purchase. You will receive the latest model rather than a refurbished mystery model. Also, your warranty will be honored by Nautilus, which may not be the case when purchasing through a third-party.

Other Nautilus Treadmills

Nautilus T614
Nautilus T616

Check Out This Years Best Treadmills:

NordicTrack Commercial 1750
ProForm Pro 2000
NordicTrack Commercial 2450
Sole F80