• All-petrol line-up is economical 
• All models offer over 40mpg
• Used diesel models most efficient 

The Rio’s line-up of small petrol engines means all cars offer claimed fuel economy of somewhere in the 40s. The entry-level 1.25-litre unit manages 45.6-46.3mpg, while upgrading to the 1.4 sees similar figures. It’s only when you add an automatic gearbox into the mix that it falls slightly, with 42.2mpg claimed. 

Most efficient of the range is the 1.0-litre turbo with 97hp, claiming up to 48.7mpg when in 2 trim. Upgrade to a GT-Line with this engine and it falls to 47.9mpg. Finally, the 116hp version of this engine ranges between 44.1mpg and 46.3mpg, with that lower figure the reserve of the automatic model. 

CO2 emissions figures are far more variable, with the 1.0-litre turbos being the cleanest, claiming between 114g/km and 124g/km. The 1.25 emits 125/126g/km while the 1.4 is the worst performer at 143-144g/km, which is really rather high for a small, low-output supermini like this. 

Unsurprisingly the Rio’s 1.4-litre diesel engine (now only a used option) provides the greatest fuel efficiency – whether in 77hp or 90hp guise. The former returns combined fuel economy of 80.7mpg and the latter 74.3mpg. Interestingly, Kia only expected around 6% of sales to be of the diesel, so it unsurprisingly was taken off sale. Also it’s worth noting that those lofty figures were pre-WLTP, so realistically they wouldn’t have quite managed those figures in everyday driving.

Is it reliable?

• Kia has a strong reputation for reliability 
• Plus a seven-year warranty 
• Should be very little to worry about 

Recent Kia products have boasted a highly impressive reliability record backed up by a seven-year/100,000-mile warranty that is transferable between owners. Infotainment systems seem to work well with few glitches that can blight other manufacturer systems, while mechanical dependability also seems to be largely impressive. 

The only recall the Rio’s been the subject of is one regarding the child locks potentially not operating on the rear doors. This will have been rectified by a dealer, if it’s a used example you’re considering.