Tax on share sale escrow interest

I was recently fortunate to partake in the sale of shares in a M&A by my employer. An amount of the sale (~15%) was held in an escrow account for warranty purposes with payments made out at 12 months and 18 months (both in the tax year following the original sale). It is my understanding that all of those original amounts became liable for capital gains at the point of shares being sold. Since the sale there were no claims against warranty and the full amount has been paid from the escrow account. In addition the escrow account was interest bearing and so interest was also paid out to myself and the other shareholders. My employer has reflected that as a revision to the price per share, suggesting that the interest would also be liable for capital gains in the previous tax year. This was unexpected to me as I would expect it to be liable for income tax (with personal savings allowance relief) in the year in which the interest was arisen. Which would be the correct interpretation here?

Hi

Please refer to CG14805.
This confirms your understanding that 100% of the sale proceeds are included in the CGT computation for the tax year of disposal and that no adjustment is made for the 15% held in the escrow account as there have been no claims against the warranty.
No adjustment should be made to the base cost of the shares regarding the interest paid on the amount held in escrow.
As you say, the interest paid from the escrow account would be taxable as income and would have the Personal Savings Allowance applied to it.
These links have general guidance on the meaning and taxation of interest – SAIM2030, SAIM2060 & SAIM2400.
You would need to speak to your employer to find out if there is a particular reason why they have increased the price per share as it may be for another reason.

Thank you