What Are Sinking Funds? (Examples + Setup Guide)
By Presusimple
Your car insurance bill arrives in March. You forgot. Again. Suddenly €480 disappears and your grocery budget is toast.
That's not an emergency—that's a predictable expense you didn't plan for. A sinking fund is money you save monthly for a specific future expense (insurance, holidays, car repairs, gifts). Divide the total cost by months until due, save that amount each month, and pay the bill from the fund without touching your emergency savings or going into debt.
What is a sinking fund?
A sinking fund is a dedicated savings category for a known upcoming expense. You set aside a fixed amount each month until you reach the target, then spend the fund when the bill arrives. Unlike an emergency fund (for surprises), sinking funds cover expenses you can name and date—annual insurance, Christmas gifts, school fees, or a vacation you've already planned.
Quick example: Car insurance is €600/year, due in 6 months. Save €100/month in a "Car Insurance" sinking fund. When the bill hits, the money is already there.
Sinking fund vs emergency fund
| Sinking fund | Emergency fund | |
|---|---|---|
| Purpose | Planned, expected costs | Unexpected, urgent costs |
| Examples | Annual insurance, gifts, travel | Job loss, medical emergency |
| Timing | You know roughly when | You don't know if or when |
| Amount | Fixed target per goal | 3–6 months of essentials |
| Priority | After mini emergency fund | Build first (€1,000+) |
Use both. Emergency fund for shocks; sinking funds for calendar expenses that would otherwise feel like shocks.
Common sinking fund categories
Start with the bills that wreck your budget every year:
Annual & semi-annual bills
- Car and home insurance
- Property taxes
- Professional licenses or union dues
- Annual software subscriptions
- School tuition deposits
Seasonal & lifestyle
- Holiday and birthday gifts
- Back-to-school supplies
- Vacation travel
- Wedding gifts (if you're in that life stage)
- Pet annual vet visit
Maintenance & replacement
- Car maintenance and tires
- Home repairs (appliances, HVAC service)
- Phone or laptop replacement fund
- Clothing refresh (work wardrobe, kids' shoes)
Rule of thumb: If you've said "I forgot that was due this month" in the last year, it needs a sinking fund.
How to set up sinking funds in your budget
Step 1: List upcoming non-monthly expenses
Scan the last 12 months of bank statements. Highlight anything that wasn't monthly but cost more than €100:
- Insurance premiums
- Gifts
- Travel
- Membership renewals
- Car service
Step 2: Calculate monthly contributions
For each expense: Total cost ÷ months until due = monthly savings
| Expense | Total | Due in | Monthly save |
|---|---|---|---|
| Car insurance | €600 | 12 months | €50 |
| Christmas gifts | €400 | 10 months | €40 |
| Vacation | €1,200 | 8 months | €150 |
| Car maintenance | €300 | 12 months | €25 |
| Total | €265/month |
Add €265 to your monthly budget as sinking fund categories—not as one blob, but as named lines so you know what each pile is for.
Step 3: Keep funds separate (mentally or literally)
Options:
- One savings account, spreadsheet tracking — simplest
- Separate savings "buckets" (if your bank supports them)
- Budget app categories — Presusimple lets you set limits per category and track balances
The method matters less than the habit: money assigned before the bill arrives.
Step 4: Spend the fund guilt-free
When car insurance is due, pay from the sinking fund—not from groceries, not from emergency savings. Then restart the monthly contribution for next year.
Sinking funds in zero-based budgeting
In zero-based budgeting, sinking funds are regular categories with monthly limits—just like rent or groceries. They ensure income minus all allocations equals zero including future bills.
Example €2,500 budget might include:
- Sinking: Car insurance — €50
- Sinking: Gifts — €40
- Sinking: Vacation — €100
- Sinking: Car maintenance — €25
That's €215/month assigned to future-you. No surprises in March.
Building your first monthly plan? Our monthly budget guide walks through category setup step by step.
Mistakes to avoid
- One giant "sinking fund" category — you won't remember what it's for
- Skipping months — annual bills don't care that you forgot in August
- Raiding funds for non-planned spending — if you dip in, replenish before the real bill
- Confusing sinking funds with emergency funds — sales and "deals" are neither
- Over-funding too many categories at once — start with 2–3 that actually hurt you yearly
FAQ
How many sinking funds should I have?
Start with 2–3 for your biggest annual surprises—usually insurance, gifts, and one maintenance category. Add more once those feel automatic. More than 8–10 categories gets hard to maintain.
Where should I keep sinking fund money?
A high-yield savings account separate from checking works well. Some people use one account with a spreadsheet; others use bank sub-accounts. Accessibility within 1–2 days is enough—you know when the bill is coming.
What if the expense amount changes?
Recalculate when you get the new quote. If insurance jumps from €600 to €720/year, adjust your monthly save from €50 to €60. Review sinking funds at your monthly budget review.
Can I use sinking funds with the 50/30/20 rule?
Yes. Treat sinking funds as part of "needs" or "savings" depending on the expense—insurance is a need; vacation sinking fund might live in wants. The 50/30/20 vs zero-based comparison explains how to combine methods.
Track sinking funds in Presusimple
Create a category for each sinking fund, set the monthly limit, and log transfers or savings the same way you track spending. Charts show whether you're on pace before the bill hits.
Pair sinking funds with daily expense tracking and a solid emergency fund for a budget that handles both surprises and predictable pain points.
Start your free 30-day trial — assign every euro, including the ones future-you will need.