Best in Class

Best in class:
Skoda Fabia Greenline 1.2 TDI - 89g/km
Volkswagen Polo 1.2 TDI Bluemotion - 91g/km
Seat Ibiza 1.2 TDI Ecomotive 3 Door - 92g/km

Best of the rest:
Ford Fiesta 1.6 TDCi Econetic - 98g/km
Renault Clio 1.5 DCI eco2 - 98g/km
Seat Ibiza 1.4 TDI Ecomotive 3 Door - 98g/km
Vauxhall Corsa 1.2 CDTI Ecoflex - 98g/km

There is now a huge scramble to get one version of each supermini below the all-important 100g/km of CO2 barrier that results in free road tax. No fewer than seven manufacturers now offer models just below the threshold, and the number can only grow. Superminis are too cheap to be viably equipped with hybrid powertrains, but improved engine efficiency and weight-saving measures will see steadily declining emissions. All the best cars in this class are diesel, incidentally.