AMG Line, M Sport, S line: what a trim really costs

AMG Line, M Sport, S line and R-Line are appearance packs. They change neither the engine, nor the gearbox, nor the fiscal horsepower. On an electric Mercedes CLA, the AMG Line pack costs €5,808 more than the base version, for the same mechanicals. The real AMG is a different car altogether.

Three Belgian terms recur below and are worth defining once. BIK (avantage de toute nature, ATN) is the taxable benefit in kind charged to anyone with private use of a company car. VRT (taxe de mise en circulation, TMC, and BIV in Flanders) is the one-off registration tax due when a vehicle first enters service, set regionally. Road tax (taxe de circulation) is the annual regional levy that follows.

AMG Line or AMG: what actually changes?

The engine, and it alone decides the bill.

AMG Line is a trim level applied to an ordinary Mercedes-Benz: redrawn bumper, sports seats, specific steering wheel, larger wheels. The car remains a CLA 200 or an A-Class A 180. Mercedes-AMG is a separate range, with its own mechanicals, its own commercial designation and its own price.

The same trap exists at the other two German brands. M Sport is a pack on a standard BMW; a BMW M, or an M Performance like the M135 xDrive, is a distinct model. S line is a pack on an Audi; the Audi S3 and the RS 3 are different cars. At Volkswagen, R-Line and Golf R follow exactly the same logic.

A buyer who confuses the two is not making a mistake of taste. He is making a mistake of invoice, and it costs money in both directions: either he thinks he has paid for mechanicals when he has paid for plastic, or he fears a performance car's servicing bill on a car that is not one.

How much does the AMG Line pack cost on a Mercedes CLA?

€5,808, and the figure does not move from one powertrain to another.

I recorded the Belgian list prices of the 2027 CLA range on 29 August 2026. Three electric versions, three times the same gap to the cent between the plain version and the AMG Line version.

A constant gap across three different powertrains is the signature of a pack priced independently of the mechanicals. The engine is the same on both sides of the column. The rest sits in an accessories catalogue.

Does S line trim increase the BIK on a company car?

Yes, and the mechanism is set out in black and white by the tax administration.

BIK is calculated on the catalogue value of the new vehicle sold to a private buyer, options included, with the VAT actually paid included, and with no account taken of discounts or rebates. The formula published by SPF Finances is: catalogue value x 6/7 x age percentage x CO2 percentage, with a CO2 coefficient between 4% and 18%.

A pack that enters the list price therefore enters the taxable base. The calculation takes one line. On an electric car emitting 0 g of CO2, so at the 4% floor coefficient, the €5,808 of the CLA's AMG Line pack produce 5,808 x 6/7 x 4% = €199.13 of extra BIK a year, or €597.40 over three years, for not one extra horsepower.

On a combustion car the CO2 coefficient is higher and the total climbs. Moniteur Automobile publishes the monthly BIK of the Audi A3 Sportback 1.5 TFSi 110 kW S tronic: €211.06 in Attraction, €230.31 in S line. Nineteen euros and twenty-five cents a month, €693 over thirty-six months, for a pack invoiced at €2,200 at purchase.

The full reasoning behind the calculation, including the exempt share for home-to-work journeys, is set out in the article on how BIK is calculated.

M Sport or a real M: where does the €24,650 gap go?

Into the engine, and Belgian tax confirms it immediately.

Moniteur Automobile publishes no separate price line for the M Sport pack on the 2026 1 Series Hatch: the range is listed there by powertrain. The M135 xDrive, on the other hand, appears as a version in its own right. The comparison between the entry model and this M Performance gives the following amounts, Brussels column, recorded on 29 August 2026.

€24,650 of list-price gap between the 116 and the M135 xDrive. €386.29 of extra monthly BIK, or €13,906.44 over three years. And €4,834 of extra Brussels registration tax, paid once but paid up front.

An M Sport pack produces none of those three lines. That is the whole difference, and it does not show up in a classified ad photograph.

The pack is paid once on the price list and every month in BIK. The mechanicals are also paid in registration tax, in tyres and at the workshop.

Does the trim level change registration tax and road tax?

No in two regions out of three, and the Flemish exception has a precise cause.

In Brussels and Wallonia, registration tax and road tax are calculated on fiscal horsepower, itself derived from cylinder capacity or engine power. The list price appears nowhere in the scale. The SPW Finances scale reads in fiscal horsepower, not in euros of invoice.

The proof sits in the figures recorded on the Audi A3 Sportback 1.5 TFSi 110 kW S tronic. Attraction at €35,100, Advanced at €36,200, S line at €37,300: all three pay €867 of registration tax and €271.39 of road tax in Brussels. The same amount, on three different prices.

In Flanders, the BIV and the annual tax include WLTP CO2 alongside fiscal horsepower, the Euro standard and the fuel. The calculation is published by the Vlaamse Belastingdienst. There, a pack that takes the wheels from 18 to 19 inches and pushes homologation up by a gram or two genuinely moves the amount. The regional simulator remains the only reference on a specific case, because CO2 depends on the exact combination of options ordered.

Remember the rule rather than the amounts: the pack costs at the moment of purchase, costs every month in BIK, and costs nothing in regional taxes as long as it does not touch homologated CO2.

Classified-ad vocabulary, term by term

A pack is recognised by one thing: the price changes, the power in kW does not. Check that column before any other.

Does an AMG Line resell better than a base trim?

I have no dated, public Belgian series measuring the resale premium of a trim pack, so I will not publish a percentage. In this segment, the figures that circulate come from forums and dealer websites, with no date and no method.

The only certain fact is an accounting one, and it is enough. The €5,808 of the pack is paid on day one, enters the catalogue value and depreciates like the rest of the car. For it to pay off, the resale would have to give it all back. No option does that.

Another mechanism does check out, however: a much-requested trim widens the pool of potential buyers and shortens the time to sell. That is a gain in liquidity, not a gain in value, and the two are often conflated in dealership conversations. Depreciation by model is treated separately in the article on which models hold their value.

Three checks before you sign

• The power in kW on both quotes. If it is identical, you are paying for a pack. If it changes, you are paying for a different car, with the registration tax and the servicing that go with it.
• The wheel diameter and the exact tyre size. A 19 or 20 inch wheel is paid for again at every set of tyres, and the price of a set does not compare from one diameter to the next.
• The WLTP CO2 of the precise configuration. That figure drives the BIK coefficient and, in Flanders, the BIV. It changes with the options, not only with the engine.

To choose a model rather than a pack, costs are set out line by line in the luxury car ranking, and the specific case of the Mercedes range is covered in the best Mercedes for premium family use.

Sources

• SPF Finances, company cars, accessed 29 August 2026: benefit-in-kind formula, catalogue value including options and the VAT actually paid, discounts and rebates not deducted, 6/7 coefficient, CO2 percentage between 4% and 18%.
• SPW Finances, road tax scale, additional decimes included, valid 1 July 2026 to 30 June 2027, accessed 29 August 2026: scale set in fiscal horsepower, with no reference to list price.
• Vlaamse Belastingdienst, accessed 29 August 2026: Flemish BIV and road tax calculated on WLTP CO2, the Euro standard, the fuel and fiscal horsepower.
• Moniteur Automobile, prices of the 2027 Mercedes-Benz CLA, recorded 29 August 2026: CLA 200 at €49,610, CLA 200 Business Line at €51,909, CLA 200 AMG Line at €55,418, CLA 250 at €52,635, CLA 250 AMG Line at €58,443, CLA 250+ at €55,055, CLA 250+ AMG Line at €60,863, CLA 350 4MATIC Business Line at €62,194, CLA 350 4MATIC AMG Line at €65,703.
• Moniteur Automobile, prices of the 2027 Audi A3 Sportback, recorded 29 August 2026: 1.5 TFSi 110 kW S tronic Attraction at €35,100 with monthly BIK of €211.06, Advanced at €36,200 with BIK of €225.40, S line at €37,300 with BIK of €230.31, Brussels registration tax of €867 and Brussels road tax of €271.39 on all three; 1.5 TFSi 85 kW Attraction at €32,500 and S line at €34,700.
• Moniteur Automobile, prices of the 2026 BMW 1 Series Hatch, recorded 29 August 2026: 116 at €34,050, BIK of €177.37, Brussels registration tax of €123, road tax of €271.39; 120 at €38,350; 118d at €38,850; M135 xDrive at €58,700, BIK of €563.66, Brussels registration tax of €4,957, road tax of €486.02.
• Moniteur Automobile, price of the Audi S3 Sportback 2.0 TFSI 245 kW, recorded 29 August 2026: €56,150, 8.3 l/100 km, 189 g of WLTP CO2, BIK and registration tax not published at that date.