Lintel crack repair

[DIYspanner]

Sandstone I believe but only decorative.

Is there any kind of filler I can use to fill the crack?

 

[RandomGrinch]

Hi,
If you're not concerned about the crack structurally, you could try:
https://www.toolstation.com/fischer-dec-premium-express-ready-mixed-cement-cartridge/p92327
However, you may need something more flexible to avoid further cracks appearing, such as:
https://www.toolstation.com/toupret-fibacryl-flexible-filler/p40082
And match colour by another means.

 

[DIYspanner]

Its occurred to me that I could a mix of some white cement, course sand for texture and colour it with some Buff mortar tone.

I'd likely have to make the crack slight wider to fill it.

 

[RandomGrinch]

Yes, that should do it
It's basically what the first product is, if you haven't got the cement and sand already.
Good luck!