YearToAvoid

2021 Mercedes-Benz GLB 250 Problems, Recalls & Reliability

Verdict

Caution

Complaint Index

60/100

#3 most-complained of 6 GLB 250 years

The 2021 Mercedes-Benz GLB 250 has a Complaint Index of 60 and ranks 3rd worst of 6 model years, earning a Caution verdict. It has 29 complaints, 11 recalls, and no reported crashes, fires, injuries, or deaths.

Complaints
29
Recalls
11
Crashes / fires
0 / 0
Injuries / deaths
0 / 0
NHTSA overall rating
Not rated
EPA combined MPG
26
23 city / 30.5 hwy

Top 2021 Mercedes-Benz GLB 250 problems

NHTSA owner complaints by component group. Groups with 15+ complaints have their own page.

  1. Other10 (34%)
  2. Engine7 (24%)
  3. Suspension, Wheels & Tires6 (21%)
  4. Electrical System4 (14%)
  5. Structure & Body3 (10%)
  6. Transmission & Powertrain3 (10%)
  7. Collision Avoidance & Cameras2 (7%)
  8. Fuel System2 (7%)
  9. Steering2 (7%)
  10. Visibility & Wipers2 (7%)

What owners report

  • Engine develops rough idling, jerking, and loud diesel-like noise on acceleration, sometimes with camshaft position faults and metal particles found in the oil filter.
  • Front axle produces clunking, thumping, and cracking noises at low speeds.
  • Tires vibrate with a flapping sound at highway speed, reported at 30,600 miles median mileage for suspension complaints.
  • Electrical system fails entirely while driving, disabling the dashboard, sometimes triggering the check engine light.
  • Windshield develops an internal crack near the rearview mirror sensor area without any impact.
  • Horn honks on its own while driving.
2021 Mercedes-Benz GLB 250 complaints: complaints filed per month6Dec 2021Jul 2022Jan 2023Aug 2023Feb 2024Sep 2025Jan 2026Apr 2026
44 complaints filed with NHTSA from Dec 2021 to Aug 2026; peak Jun 2025 (6).

2021 Mercedes-Benz GLB 250 recalls

11 NHTSA recall campaigns list this model year.

  1. NHTSA 26V481000Jul 24, 2026Structure & Body310,667 vehicles

    Latches/locks/linkages:doors:lock

    Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2021 CLA, 2019-2022 A-Class, 2022-2023 C-Class, 2024 CLE, 2020-2026 GLA/GLB, and 2023-2024 GLC vehicles. Please refer to MBUSA's recall report for specific model information. The micro-switch in the driver's door lock may corrode and fail to detect an open door, preventing the electronic parking brake or "Auto-Park" feature from engaging automatically. This may result in a vehicle rollaway.

    Risk: A vehicle rollaway increases the risk of a crash or injury.

    Remedy: Dealers will replace the driver's door lock, free of charge. Owner notification letters are expected to be mailed September 18, 2026. Owners may contact MBUSA customer service at 1-800-367-6372. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning July 31, 2026.

  2. NHTSA 22V679000Sep 12, 2022Brakes4 vehicles

    Electronic stability control (esc):control module

    Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 GLB250 vehicles. The Electronic Stability Program (ESP) unit may be damaged, which can result in disabled anti-lock brakes (ABS), disabled electronic stability control (ESC), and an electrical short circuit.

    Risk: Disabled anti-lock brakes and electronic stability control can increase the risk of a crash or injury. An electrical short circuit increases the risk of a fire.

    Remedy: Dealers will replace the ESP unit, free of charge. Owner notification letters were mailed October 28, 2022. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2022090009.

  3. NHTSA 22V365000May 20, 2022Electrical System242,722 vehiclesOver-the-air fix

    Electrical system:software

    Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2022 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, AMG GT-Class, C-Class, E-Class, S-Class, SL-Class, GLC-Class, CLS-Class, GLB-Class, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. An error in the communication module's SIM card software can cause a mobile network connection failure, disabling the emergency call (eCall) system.

    Risk: A disabled eCall system would prevent a vehicle occupant from contacting the emergency services call center in an emergency, potentially delaying emergency responders and increasing the risk of injury.

    Remedy: The communication module software will be updated through an Over-the-Air (OTA) update or by a dealer, free of charge. Owner notification letters were mailed July 8, 2022. Owner notification letters will be mailed in phases, on July 8, 2022, May 17, 2024, July 29, 2024, and September 27, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's numbers are for this recall is 2022060005 and 2023110006.

See all 11 recalls for the 2021 Mercedes-Benz GLB 250 →

2021 Mercedes-Benz GLB 250 fuel economy and fuel cost

City
23 MPG
Highway
30.5 MPG
Combined
26 MPG
Annual fuel cost (EPA)
$3,050
15,000 mi/yr
Fuel
Premium
Current regular gas
$4.32/gal
national avg.

EPA figures; median across configurations of this model year. Estimate your own cost with the fuel cost calculator.

2021 compared with other GLB 250 years

Complaint Index by model year (0 = fewest issues, 100 = most)0255075100202020212022202320242025
Complaint Index: 0 = fewest issues, 100 = most, relative to other years of this model. Avoid Caution Good Best
YearVerdictIndexComplaintsRecallsMPG
2020Avoid100532026
2021Caution60291126
2022Avoid8011126
2023Good4011126

All Mercedes-Benz GLB 250 years: best and worst →

Frequently asked questions

Is the 2021 Mercedes-Benz GLB 250 reliable?
Based on NHTSA owner complaints and recalls, the 2021 GLB 250 carries a Complaint Index of 60 and a Caution verdict, ranking 3rd worst among 6 model years. It has fewer complaints than the 2020 model but more recalls-related issues than several other years.
What are the most common problems with the 2021 GLB 250?
Engine problems make up 24% of complaints, followed by suspension, wheels and tires at 21% and electrical system issues at 14%. Owners also reported structure/body and transmission/powertrain concerns.
Does the 2021 GLB 250 have recalls?
Yes, NHTSA lists 11 recalls for the 2021 GLB 250, covering airbags, brakes (ESP unit), electrical/multimedia software, a rearview camera update, a suspension level sensor linkage, and a door lock issue shared with other Mercedes-Benz models.
How does the 2021 GLB 250 compare to other GLB 250 years?
The 2021 model's Complaint Index of 60 is lower than the 2020 GLB 250's index of 100, which is the worst year, but higher than the 2023 GLB 250's index of 40, which carries a Good verdict.
What mileage do problems typically appear at on the 2021 GLB 250?
NHTSA data shows a median mileage of 30,600 miles at failure for the 2021 GLB 250 overall, matching the median mileage reported for suspension, wheels and tires complaints.

Sources: NHTSA Office of Defects Investigation complaint and recall databases; U.S. EPA fuel economy data; NHTSA 5-Star Safety Ratings. Complaints are unverified owner reports.

Data updated Sep 24, 2026. Read the methodology and data sources. The Complaint Index is based on NHTSA owner complaints and recalls; it is not a reliability rating.