Somewhere around month five of a pregnancy, a spreadsheet gets made. It has a tab for the nursery, a tab for the hospital bill, a column of estimates copied from a forum. It is a good spreadsheet. It is also, almost always, the last time anyone opens it.
Nobody lacked discipline. A plan built for a calm evening met a household that had not slept in a week. The budget has to work on the worst day, not the planning day, or it does not work.
So this is the version I would build now, knowing what the first year is like.
Separate the one-time costs from the monthly ones
Two kinds of money leave when a baby arrives, and they need different handling.
The one-time costs are the ones the spreadsheet is good at: crib, car seat, stroller, the deductible on the birth itself. They are large, they happen once, and the right tool is a savings goal with a target and a date. Set it, let a share of each paycheck flow into it, and stop thinking about it.
The monthly costs are the ones that quietly eat a budget: diapers, formula or feeding supplies, wipes, the pharmacy runs, the extra laundry, and later childcare. These are small, frequent, and they never stop, which is the exact shape a daily allowance is built for.
Give the baby a category, or three
In Buoy each spending category earns a daily allowance and the balance counts up when you spend less than it. For a new baby I would create three: baby essentials (diapers, wipes, feeding), baby health (copays, prescriptions, the pharmacy), and childcare if you have it.
Set each to a monthly figure that feels roughly right. It will be wrong. That is fine, because the point of the first two months is to find out what the real number is, and a count-up category tells you that without a spreadsheet: if the balance keeps climbing, the allowance is high; if it keeps going negative, it is low. Adjust once, in month three, when you can think again.
Every purchase syncs from your bank and lands in the right category, either by a rule you wrote once (“Target on a Sunday morning is baby essentials”) or by the AI when the rule does not fit. Nobody is typing receipts at 2 a.m.
Both parents, one budget, no arguing about the app
The math rarely breaks a baby budget. What breaks it is one person setting it up while the other spends against it without seeing it.
Buoy’s family sharing puts both of you on the same budget with roles. One person can own it and change the allowances; the other can be a budget admin with the same powers, or read-only if they just want to see where things stand before a shopping trip. Each person keeps their own login and their own bank connections; the shared budget is the thing you look at together.
In practice this means the question “did we already buy wipes this week?” has an answer on either phone, which is a smaller thing than it sounds until you have had the argument.
The numbers, and why I will not give you a total
You will find articles that put a figure on the first year. They are guessing, and the range is so wide that the number is useless: a family with insurance that covers the birth and a grandparent for childcare is living in a different budget from a family paying a deductible and a daycare waitlist deposit.
What I can tell you is the shape. The one-time costs front-load into the last two months before the due date. The monthly essentials settle into a rhythm within about eight weeks. Childcare, when it starts, is usually the largest single line in the budget, larger than everything else baby-related combined, and it deserves its own category from the first invoice.
Set it up before the baby comes
Do it in the calm months: three categories, one savings goal, both parents on the budget. Then leave it alone. The app will keep the numbers current from your bank while you are busy with the far more important thing.
Buoy has no ads and never sells your data. Family sharing is part of Premium, and the trial needs no card, so you can set the whole thing up before deciding.