If you are a paying parent and the children stay with you overnight you are entitled to claim a discount on your maintenance calculation according to the following discount schedule
|Number of nights||Fraction to subtract|
|52 to 103||One-seventh|
|104 to 155||Two-sevenths|
|156 to 174||Three-sevenths|
|175 or more||One-half|
Note that there are 365 nights in a year, half of which is 182.5.
Even if the children stay overnight with the paying parent for: 175, 176, 177, 178, 179, 180, 181, or 182 nights a year the paying parent must still pay HALF of their calculation.
Further reading: a case involving the CMS refusing to accept a shared care situation where a father had his children in excess of 175 nights a year:
Successful appeal to the Upper-tier Tribunal in which the appellant father contended that since he shared care of his son equally he should not be treated as a non-resident parent and should not be liable for a CMS assessment.
The father (“F”) appealed to the First-tier Tribunal (“FTT”) against a decision of 27 March 2014 made by the CMS requiring him to pay £55.14 pw in respect of his son (“S”).
This was calculated on the basis that he cared for S on 175 nights or more. F contended that he shared care of S equally with M and should not therefore be treated as a non-resident parent (“NRP”). The consequence of such would be that F should not have been liable for a CMS assessment at all.
Having failed in appealing the decision to the FTT, F succeeded in the Upper-tier Tribunal (“UTT”).
JS v Secretary of State for Work and Pensions and another (CSM) (Child support – maintenance assessments – calculations)  UKUT 296 (AAC):
LINK to Family Law Week case
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