Share incentive plan

[Nick_C]

Just changed jobs and have been offered to participate in a share incentive plan, being able to purchase £150 a month, which will only cost around £85 due to tax advantages. What I also want to check is as I am also liable for child benefit tax will the purchase of these also reduce my adjusted income and therefore reduce the child benefit tax owed?
Have to hold for at least 5 years to keep the tax advantages but seems a good option.

Nick