BestCarRank
Mercedes-Benz

2021 Mercedes-Benz GLB 250

Problems, Recalls & Reliability Report

Below Average

Quick Summary

The 2021 Mercedes-Benz GLB 250 has 44 owner complaints filed with NHTSA — that's 1.8x the segment average of 25. The most common issue is other problems (23% of all complaints), specifically: on september 3, 2022 while traveling east on al highway 110 the sunroof exploded as i was driving. notified montgomery county sheriff department but they refuse to do a report because it wasn’t an accident. the dealership said something had to hit the sunroof for it to shadder. explained to the serv. There are 4 recalls issued for this model year.

44

Total Complaints

4

Recalls Issued

/5

Safety Stars

1.8x

vs Segment Avg

Known Problems(top 5 of 8)

OTHER

10 complaints
23%
  • On September 3, 2022 while traveling east on AL highway 110 the sunroof exploded as i was driving. Notified Montgomery county sheriff Department but they refuse to do a report because it wasn’t an accident. The dealership said something had to hit the sunroof for it to Shadder. Explained to the serv
  • The car has 29,000 miles and I took it on a two day trip across part of the country. It was driven hard but had a oil change before leaving. After arriving home it started to sputter and have no "energy". I had the cabin filter and engine filter changed and another oil change just in case. took
  • My fuel tank cover would not open. Car was under warranty so MB was able to replace the motor of the fuel cap release. Problem, there is no manual release for the fuel cap so if you are low on fuel and need to fill up, you would be stranded. They need a manual release for the fuel cap for safety.
Typical onset: 50K miles Est. repair: $500

On September 3, 2022 while traveling east on AL highway 110 the sunroof exploded as i was driving. Notified Montgomery county sheriff Department but they refuse to do a report because it wasn’t an accident. The dealership said something had to hit the sunroof for it to Shadder. Explained to the serv

— NHTSA complaint filing

Recalls (4)

ELECTRICAL SYSTEM:SOFTWARE05/02/2021

Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2016 - 2021 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, GT-Class, C-Class, E-Class, S-Class, CLS-Class, SL-Class, B-Class, GLB-Class, GLC-Class, and G-Class vehicles. Please refer to the Part 573 report for specific vehicle model details. The software design of the communication module may fail to communicate the correct vehicle location for the emergency call system (eCall) in the event of a crash.

Risk: Failure of the eCall system may result in emergency responders being dispatched to the wrong location, increasing the risk of injury following a crash.

Fix: MBUSA will notify owners, and the communication module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. The recall began March 12, 2021. Owners may contact MBUSA customer service at 1-877-762-8267. MBUSA's number for this recall is 2021020025.

Fuel Cost Calculator for 2021 Mercedes-Benz GLB 250

Live EIA prices
Per year
$1,847
Per month
$154
Per mile
15.4¢
MPG
26
City driving (worst-case MPG)
$2,087/yr
Highway driving (best-case MPG)
$1,549/yr

Based on EPA fuel-economy ratings and EIA weekly retail prices (2026-07-20). Real-world cost varies with driving style, trim/engine, terrain, and traffic.

5-Year Gas Price History

EIA weekly retail data · 2021 → today
Current
$4.00
5-year low
$2.78
5-year high
$5.01
Since 2021
+27%

Source: US Energy Information Administration weekly retail gasoline prices.

Estimated Insurance Cost for 2021 Mercedes-Benz GLB 250

Estimate only, not a quote. Modeled from NAIC + HLDI averages for a hypothetical 35-year-old driver with clean record + full coverage. Your actual quote depends heavily on your age, driving history, credit, ZIP code, and insurer.
Full coverage / year
$2,250
Full coverage / month
$188
Liability only / year
$710
vs US avg
+34%
How this estimate is calculated
US base full-coverage premium$1674
× state (US)1.00x
× vehicle class (sedan-luxury)1.28x
× theft risk1.00x
× safety rating1.00x
× vehicle age1.05x
= Full coverage estimate$2250

Coverage assumed: 100/300/100 liability + comprehensive/collision, $500 deductibles. Data sources: NAIC 2024 + HLDI loss studies.

Maintenance & Warranty

Recommended Mercedes-Benz GLB 250 Service Intervals

Oil change
10K mi / 12 mo
Tire rotation
10K mi
Brake fluid
24 months
Transmission fluid
40K mi
Engine coolant
150K mi
Spark plugs
60K mi
Cabin air filter
20K mi
Engine air filter
40K mi
Differential (AWD/4WD)
40K mi

Service A / Service B alternating schedule. Requires MB-approved oil (229.5 spec typically).

"Severe service" conditions (heavy towing, extreme temps, city stop-and-go) typically halve these intervals. Always consult your vehicle's owner's manual for the authoritative schedule.

Mercedes-Benz New-Vehicle Warranty Coverage

Bumper-to-bumper (basic)
4 yr / 50K mi
Powertrain
4 yr / 50K mi
Hybrid/EV battery
10 yr / 155K mi
Corrosion (rust perforation)
4 yr / 50K mi
Roadside assistance
4 yr / unlimited mi

EQ EV battery warranty is 10 years/155,000 miles

These are the terms for a new Mercedes-Benz. If you're buying a used 2021 GLB 250, remaining coverage is usually pro-rated from the vehicle's original in-service date. Not all coverage transfers between owners — check with a Mercedes-Benz dealer for VIN-specific remaining warranty.

Estimated Repair Costs

OTHER(~50K mi)
$500
ENGINE(~50K mi)
$500
SUSPENSION(~50K mi)
$500
ELECTRICAL(~50K mi)
$500
TRANSMISSION(~50K mi)
$500

Estimates based on average reported repair costs. Actual costs vary by location, shop, and severity.

🔍 Pre-Purchase Inspection Checklist

Based on 44 owner complaints for this specific year, here's what to check or ask about:

  • OTHER: On September 3, 2022 while traveling east on AL highway 110 the sunroof exploded as i was driving. Notified Montgomery county sheriff Department but they refuse to do a report because it wasn’t an accident. The dealership said something had to hit the sunroof for it to Shadder. Explained to the serv

    Typically appears around 50K miles. Repair cost ~$500

  • ENGINE: We purchased a brand new Mercedes GLB in January 2021, I noticed the car started to shake. On our way leaving Zion National Park, the car started shaking really hard and the engine light turned on. The car wouldn't accelerate. We had to pull over on the side of the road. We barely made it to the dea

    Typically appears around 50K miles. Repair cost ~$500

  • SUSPENSION: This vehicle was purchased new, in cash, from the Mercedes-Benz dealership in Bellevue, WA. It was delivered to me, without being warned about the car being equipped with summer tires, the state of Washington has continuous rain, snow, and ice in a regular basis throughout the years, summer tires ar

    Typically appears around 50K miles. Repair cost ~$500

  • ELECTRICAL: The contact owns a 2021 Mercedes-Benz GLB250. The contact received notification of NHTSA Campaign Number: 21V354000 (Back Over Prevention, Electrical System) however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had

    Typically appears around 50K miles. Repair cost ~$500

  • RECALLS: Verify all 4 recalls have been completed — free at any Mercedes-Benz dealer
  • General: Get a pre-purchase inspection from an independent mechanic ($100-$200)

Mercedes-Benz GLB 250 — Year Comparison

How does 2021 compare to other years? Fewer complaints = more reliable.

Full years-to-avoid analysis →

NHTSA Safety Rating

No NHTSA safety rating available

At a Glance

Complaints
44
Recalls
4
Fire reports
0
Crash reports
0
Injury reports
0
Segment avg
25

Check a Specific VIN

See recalls for YOUR 2021 Mercedes-Benz GLB 250