When dealing with a company whose accounting period is 01/01/2016-31/12/2016, reviewing the AIA limits screen under Assets, Capital Allowances, Annual investment Allowance the year end apportionment exceeds the £200,000 AIA limit and the Max AIA using days is shown as 200,548.

HMRC Guidance

HMRC guidance states that this is calculated as:

Define the number of Days to apportion the AIA by (D)
If No. of AP days = 366 then D = 366 Else D = 365
Where the AP straddles 01/04/2012, 01/01/2013 or 01/01/2016 D = 365"

How HMRC are calculating this

(200,000/366)*366 giving a limit of 200,000.

How the software is calculating this

(200,000/365)*366 = 200,548 (rounded)

We have reviewed this and agree that HMRC's method is correct. We will look to resolve this in a future version of Sage Corporation Tax.

This should only affect 12 month periods from the start of the calendar year with clients who have also exceeded their annual investment allowance limit.

To resolve this, you'll need to manually restrict your AIA claim to the £200,000 limit