Hi,
A declaration cannot be made where a husband and wife or civil partners own property as beneficial joint tenants. In these circumstances the couple do not own the property in shares, they are jointly entitled to the whole of both the property and the income.
This is distinct from a situation where a husband and wife or civil partners own property as beneficial tenants in common where they are each entitled to specific shares in the property and the income arising.
If you wish to split the income unequally and make a declaration to that effect you will need to change from joint tenants to tenants in common.
TSEM9850 - Property held jointly by married couples or civil partners: Form 17 rule - declaration must reflect reality
Thank you.