Notional spending begins with being provided with something of value. When the value is over £50, this is also a donation.1
You should work out the value of what has been provided as notional spending in the same way as you work out the value of a non-monetary donation.
If an employer seconds a member of staff to your campaign, you must record their gross salary and any additional allowances as notional spending.
You do not need to include the employer’s national insurance or pension contributions. You will need to include the value of any expenses, such as travel or food, that you or the employer refunds.