Priced from £36,535, the electrified S-Max commands a minimal premium over the equivalent diesel-powered model and is said to offer the same space and flexibility.
The larger Galaxy will also be offered with the petrol-electric powertrain, priced from £38,695 and available only in top-rung Titanium trim.
The MPVs shares their running gear with the recently launched Kuga Hybrid SUV, pairing an Atkinson-cycle 2.5-litre four-cylinder petrol engine with an electric motor for combined outputs of 187bhp and 148lb ft.
Both power units send their reserves to the front axle through an eight-speed 'power-split' automatic gearbox.
Electricity generated under deceleration is stored in a liquid-cooled 1.1kWh battery that provides a power boost for the engine as needed or can be used to cover "short distances" with the engine off.
To make room for the second battery under the boot floor of the S-Max, Ford rerouted the exhaust system, so with the second and third rows of seats folded flat, the S-Max Hybrid offers 2200 litres of load space - the same as the ICE-only models.
The S-Max Hybrid is capable of 43.5-44.1mpg on the WLTP combined cycle, depending on spec. That's roughly in line with the 2.0-litre Ecoblue diesel, but it emits less CO2, at 147-148g/km. The Galaxy manages 43.5mpg and emits 148g/km.
Both cars come with EV-specific functions built into their infotainment systems, including a Brake Coach that encourages maximum energy recuperation and an EV Coach that tells the driver which power source is being used.
The hybrid MPVs will be built at Ford's plant in Valencia, Spain, following a £36.7 million investment in preparing the facility to produce electrified vehicles. Customer deliveries are due to begin in April.