In Allure trim, the 508 SW has a fairly gulpsome £36,545 price before options (our test car came in at £39,420 with a modest set of options, including a £300 7kW charge capacity that ought, to our mind, be standard).
But as is the way of things, Peugeot will attempt to put one on your driveway for a figure that looks much lower – £370 a month after a £7k deposit and £13,000 balloon payment four years later assuming 6000 miles a year. Your company might have better luck. In which case, the 29g/km rating might be tax tempting.
Assuming the right use case, you might seldom need to fuel the plug-in 508, if your commute is short enough. And if you start with a completely flat drive battery, in mixed driving you should see a return approaching 45mpg – more, the harder you try. But less, in our experience, than you’d see in with VW’s (slower, admittedly) pure petrol 1.5 Arteon.