Britain’s biggest building society, the Nationwide, is introducing changes to the travel insurance provided to many of its FlexPlus account holders that means they will not be covered should they choose not to wear a helmet while riding a bike on a trip.

In a booklet sent out to account holders benefiting from the cover, the Swindon-based business outlined changes to cover that will come into effect on 21 September.

While there’s some expansion of coverage for cycling – the previous wording exclude “off road biking” but now includes riding on “bridle ways and forest roads,” the stipulation that a helmet must be worn is new.

The previous exclusion of “BMX or off road biking” has now been changed to “BMX or on downhill or extreme trails.”

So, if you’re a Nationwide customer and you’re on holiday in Paris and rent a Vélib’ you won’t be covered if something happens, unless you fancy packing a lid in your luggage or borrow or buy one while there.

Ditto in Amsterdam or Copenhagen, where in contrast to the UK, it’s noticeable that most people who use bikes to get around do so bare-headed.

We have asked Nationwide to clarify the reasons behind the requirement for people cycling to wear a helmet to benefit from its insurance cover but are yet to hear back from them.

But Twitter user – and Natiowide account holder – Wolf Simpson tweeted a link to a BikeBiz article about the change, saying: “As a customer I'm disgusted & appalled in this! So you think a helmet will be needed in Netherlands?”

Apparently, they do.

A helmet will be needed if cycling in the Netherlands to be covered by the travel insurance from the 21 September. Steve — Nationwide UK (@AskNationwide) July 20, 2017

Writing on BikeBiz, cycling author and journalist Carlton Reid noted: “The FlexPlus travel insurance is underwritten by UK Insurance Ltd. which also underwrites travel insurance policies for NatWest, Lloyds and TSB – these policies do not contain the "Helmet must be worn" clause.”

Let’s hope a precedent hasn’t been set.