Every time you log a shared expense, you should not have to negotiate the split. If you and your co-parent have agreed that medical expenses are 50/50 and school fees are 60/40, that agreement should apply automatically — every single time, without discussion.
That is the idea behind intelligent expense rules: set the percentage once, and have it applied automatically to every relevant expense from that point on. No negotiation. No manual calculation. No arguments.
Category Rules
A category rule applies a specific split percentage to every expense in a given category. For example:
- Medical & Dental: 50/50
- Education: 60/40
- Sport & Extracurriculars: 70/30
- Clothing: 100/0 (each parent covers their own time)
- Travel: 50/50
When you log a dental check-up and assign it to the Medical category, the 50/50 split is applied automatically. When you log a school excursion under Education, 60/40 is applied. No decisions needed at the time of logging.
Child Rules
A child rule applies a specific split to all expenses for a particular child, regardless of category. This is useful when:
- One child has significantly higher medical needs
- One child was enrolled in activities by one parent who agreed to bear a higher share
- Different custody arrangements mean different cost distributions per child
Category Overrides Child
When both a category rule and a child rule exist for an expense, the category rule takes precedence. This means you can set a default per-child split but override it for specific expense types — giving you fine-grained control without complexity.
The goal is to make the right split the default — so the only time you have to think about percentages is when you are setting up the rule, not every time you log an expense.
Setting Up Rules as a Co-Parent
Rules work best when both parents agree on them upfront. The process:
- Sit down (or message) and agree on splits for each category
- One parent creates the rule in your shared system
- The other parent receives a notification and can agree or dispute
- Once both parents have acknowledged the rule, it becomes the default
If circumstances change — income, custody, a child's needs — either parent can propose a new rule, which the other parent can accept or dispute.
What Happens Without Rules
Without automatic rules, every expense requires a split decision. Over a year, a family with two children might log 150 to 300 shared expenses. That is 150 to 300 opportunities for negotiation, disagreement, and conflict. Rules eliminate almost all of those decision points.
The best co-parenting financial system is one where both parents spend their energy on their children — not on spreadsheets and arguments about percentages.