Information checked: 13 October 2026.
Service your Mercedes when its dashboard service indicator or vehicle-specific maintenance schedule says it is due, using the earlier applicable time or mileage limit. There is no single mileage figure that suits every engine, model year and powertrain. Check your next due date even if the car covers few miles.
Start with your service display and handbook
Many Mercedes cars use ASSYST PLUS to identify the next service and its remaining time or distance. Find the maintenance menu using your own handbook, photograph the message and give the workshop your registration, mileage and last service date. The service letter describes maintenance scope; it does not explain a separate warning light.
Use the model-specific Mercedes owner manual rather than instructions for a different generation. A diesel estate, an AMG petrol car and an electric EQ model can have different requirements. If the display and paperwork disagree, ask the garage to reconcile them before resetting anything.
What Service A and Service B mean
Mercedes-Benz describes Service A and the more comprehensive Service B as depending on age or mileage. The service letter is a starting point for an estimate, not a complete list of every additional item due. Ask for the maintenance sheet applicable to your vehicle identification number.
For a combustion-engine car, distinguish routine oil and filter work from spark plugs, transmission maintenance and other scheduled jobs. Their due dates can differ. An electric Mercedes has a different maintenance scope and does not need an engine oil change.
Low mileage does not remove calendar deadlines
An occasionally driven Mercedes may reach its time limit before its mileage limit. Long storage periods and repeated short journeys are useful information for the technician. Tell the garage how the car is used, not simply what the odometer shows.
If your own schedule says maintenance is due by a particular month, staying under the distance limit does not extend that date. Conversely, a high-mileage commuter can reach the distance limit first. Record both deadlines after each service.
An MOT cannot replace scheduled servicing
The initial MOT failure rate was 26.75%. ( DVSA, April–June 2026; Great Britain Class 3 and 4 tests, all makes.)
That statistic describes test outcomes, not the effectiveness of a particular service programme. An MOT assesses specified roadworthiness items on the day; it does not supply oil, filters or preventive maintenance. A Mercedes can pass its test while still being overdue for servicing.
Make the service quotation specific
Gather the latest invoice, digital service report, dashboard message and unresolved advisories before booking. Ask the garage to separate scheduled work from recommendations and repairs that need your authorisation. This makes quotations easier to compare and avoids assuming that every job is included in an A or B service.
Book before the deadline and allow time for any work the inspection identifies. After collection, retain an itemised invoice showing what was completed. A reset reminder alone is not evidence that maintenance was performed.
A worked example: time limit versus mileage limit
Imagine two owners with the same vehicle-specific schedule. One makes short local trips and adds relatively little mileage; the other commutes long distances. The first may reach the calendar deadline with plenty of miles left on the indicator, while the second reaches the distance deadline before that month arrives. Both should book according to the earlier applicable limit. This is an illustration of the decision, not a claim that every Mercedes has the same interval.
Now suppose the first owner bought the car with an invoice showing only an oil change. Before treating that as a complete service, compare the work with the maintenance sheet for that visit. The next service may need to account for an item missed previously. A later dashboard due date cannot establish what was actually fitted or checked. Resolving the discrepancy before booking prevents an incomplete history from being repeated.
Additional maintenance needs its own timeline
Create a second column in your records for jobs that sit outside the main service cycle. Depending on the vehicle these may involve different filters, ignition components, drivetrain fluids or other maintenance. Write the last completion date and mileage against each item, then ask the garage to identify the next requirement from the manufacturer schedule. Do not copy an interval from a different engine or transmission.
This also helps when comparing quotes. One workshop may have included an additional scheduled operation that another quote leaves out. Ask both to state the scope before comparing the total. If the car has a service contract or particular warranty conditions, check those documents separately so the booking satisfies the agreement as well as the vehicle schedule. Do not assume that every independent appointment renews a manufacturer roadside-assistance package.
What to do when the service is already overdue
Contact the garage with the precise amount of time or mileage overdue and ask for the earliest suitable appointment. There is no reliable universal grace period that guarantees no harm to every model. Describe any warning messages and current symptoms so the workshop can advise whether normal use, limited use or recovery is appropriate pending the visit.
A car that feels smooth still needs the overdue maintenance resolved. Avoid clearing the reminder yourself merely to stop the message appearing: that can remove useful evidence without completing the job. After the visit, check the next deadline and retain the maintenance record. If you are changing garages, pass the history on so the new technician can identify what is due rather than start from assumptions.
Keep the due date visible between services
Put the next time and mileage limits in a place you will actually check, such as a calendar reminder and your vehicle record. Revisit the mileage countdown before a long journey, because a trip can bring the limit forward. Tell the garage if the car has changed use since its last appointment. A vehicle moving from occasional weekend drives to daily commuting needs its existing schedule followed against its new mileage pattern. The appointment should account for that change without guessing a different service interval from an unrelated Mercedes model.
Sources and further reading
Summary
Set the deadline from your Mercedes maintenance schedule, then confirm the additional items due alongside its A or B service. For model-specific servicing at Godstone Mercedes Ltd in Godstone, with owners travelling from Croydon, explore the service options below.
