CGT on Inherited Plot with Planning

My siblings and I have sold a plot of land attached to our late mother property. We have probate and we managed to apply and win planning permission for a house on this plot. How do we calculate CGT for this gain we received probate in July 21 and create a deed of appropriate in April 24

Hi,
Where the asset is held by an individual, this gain will normally be taxable at 20% to the extent that it falls above the higher rate income tax threshold (10% to the extent it falls within your basic rate band).
The higher 28% CGT rate which applies to disposals of residential property will not apply to a disposal of bare land, even if it already has planning permission for residential property to be built, but would apply if what they are selling is already residential property.
Definition of what is or is not residential property can be found at: CG73550 - Residential Property gains
I would also refer them to our help sheet at :
HS282 Death, personal representatives and legatees (2024) - GOV.UK (www.gov.uk).
In this case any CG would be split equally by all parties involved.
Thank you.