Parkers overall rating: 4 out of 5 4.0

Miles per pound (mpp) Miles per pound (mpp)

Petrol engines 6.9 - 11.0 mpp
Diesel engines 10.0 - 11.9 mpp
Low figures relate to the least economical version; high to the most economical. Based on WLTP combined fuel economy for versions of this car made since September 2017 only, and typical current fuel or electricity costs.

Fuel economy

Petrol engines 32.1 - 51.4 mpg
Diesel engines 49.6 - 58.9 mpg
  • Diesel engines claim impressive fuel economy
  • Lack of hybrid or electric version stops score from being higher
  • Relatively inexpensive servicing and insurance 

Of the diesel engines on offer, the 115hp 1.6-litre diesel comes out best for fuel economy, returning a combined 70.6mpg (68.9mpg for the DSG auto version).

The least-efficient diesel – although still some way more frugal than most petrol engines – is the 184hp 2.0-litre diesel, returning 62.8mpg (61.4mpg for the DSG auto version).

The most efficient petrol engine meanwhile, is the 115hp 1.0-litre, capable of 64.2mpg. In comparison, the least-frugal petrol is the 300hp 2.0-litre Cupra model, returning up to 41.5mpg on average (40.9mpg for the six-speed manual) – reasonable figures for such a powerful car. 

If you’re after the most eco-friendly SEAT Leon ST then head for the 115hp 1.6-litre diesel engine. Claimed CO2 emissions are 105g/km for the manual version and 109g/km for the automatic. The 150hp 2.0-litre diesel version isn’t far behind, producing 112g/km of CO2.

The least eco-friendly SEAT Leon ST is, predictably, the 300hp 2.0-litre Cupra version, producing 158g/km of CO2 in manual form and 156g/km in DSG automatic guise. 

  • Solid reliability record for the Leon ST
  • Many parts shared with other VW Group cars
  • Only one minor recall since Leon ST was launched

SEAT Leon ST reliability should be broadly similar to other medium-sized vehicles from the Volkswagen Group – that is to say, solid but not completely faultless.

READ: We ran a SEAT Leon for four months - see if anything went wrong with it here.

The automatic DSG gearboxes have been known to develop faults – although usually out of the standard warranty period – and are usually very expensive to repair. Thus, if you’re planning on running an automatic Leon ST beyond the standard manufacturer guarantee, think about purchasing an extended warranty. 

A number of SEAT models (including the Leon) were recalled in 2016 over an issue where the child lock may disengage without warning. The fault affected cars built between 25 November 2015 and 14 April 2016. 

Ongoing running costs

Road tax (12 months) £0 - £205
See tax rates for all versions
Insurance group 12 - 36
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