Irregular medical costs worksheet

Purpose, who it is for and how to use it

Purpose: turn a year of uneven medical costs into one steady amount per paycheck or per month.

Who it is for: anyone with or without insurance, whether you use a health savings account (HSA), a health flexible spending arrangement (FSA), both a limited-purpose FSA and an HSA, or ordinary savings.

How to use it:

Gather your plan's Summary of Benefits and Coverage (it lists the deductible and out-of-pocket maximum), last year's receipts or pharmacy history, and your benefits enrollment materials.
Fill in Part A with costs you can name. Use whole dollars.
Work through Part B line by line.
Use Part C before you choose an FSA election or HSA contribution.
Redo the sheet at open enrollment, when your plan or job changes, or after a large bill.

Write in pencil. Do not write account numbers, member IDs or diagnoses on this page.

Part A: Costs you can name for the rest of this plan year

Mark each item O if your health plan's out-of-pocket maximum does not cover it (most dental and vision costs, over-the-counter items, medical travel, services the plan does not cover) or C if it is cost sharing for covered medical care (copays, coinsurance, deductible).

Item	For whom	Month expected	O or C	Estimated cost ($)
Prescriptions (monthly cost × months left)
Dental cleanings or dental work
Eye exam, glasses or contacts
Specialist or therapy visits
Lab work or imaging
Planned procedure
Over-the-counter medicines and supplies
Medical equipment (for example, hearing aid batteries, test strips)
Mileage, parking and tolls for care
Other

Total of O items: $________ → copy to line 1

Total of C items: $________ → copy to line 2

Part B: The worksheet

Line	What to enter	Your amount ($)
1	Planned costs outside your plan's out-of-pocket maximum (Part A, O items)
2	Planned cost sharing for covered medical care (Part A, C items)
3	Cushion for unplanned covered care (many people use their deductible)
4	Covered-care total: the smaller of (line 2 + line 3) and your in-network out-of-pocket maximum
5	Yearly target: line 1 + line 4
6	Money already set aside for medical costs (HSA balance, FSA carryover, savings set aside for this)
7	Employer contributions you expect this year (HSA deposits, FSA employer credits)
8	Still to save: line 5 − line 6 − line 7 (enter 0 if negative)
9	Paychecks or months left in the year
10	Amount to set aside each time: line 8 ÷ line 9, rounded up to the next whole dollar

The formula

Line 4 = min(line 2 + line 3, out-of-pocket maximum)
Line 5 = line 1 + line 4
Line 8 = max(0, line 5 − line 6 − line 7)
Line 10 = ceiling(line 8 ÷ line 9)

Units: U.S. dollars per year, except line 9 (a count) and line 10 (dollars per paycheck or per month).

Assumptions: the out-of-pocket maximum caps what you pay in a plan year for covered, in-network care. It does not include premiums, and it usually does not include care outside your plan's network or services your plan does not cover, so those belong on line 1. If your family plan also has a per-person limit, use whichever applies to the people you are budgeting for. If you have already paid toward this year's out-of-pocket maximum, use only the part that is left.

Rounding: round line 10 up so the total is not short. Your employer calculates payroll deductions for an FSA or HSA its own way; small differences are normal.

Missing values:

No insurance, or care will be out of network: skip the cap. Line 4 = line 2 + line 3.
Do not know your out-of-pocket maximum: find it in your Summary of Benefits and Coverage or ask your plan. Until then, use line 2 + line 3 and mark the result "uncapped."
No cushion: enter 0 on line 3. The result covers only planned costs.

Edge cases:

If line 8 is negative, you already have enough. Enter 0, and do not withdraw the extra unless you are sure you will not need it.
If line 2 + line 3 is more than your out-of-pocket maximum, the cap applies. Costs on line 1 still add on top.
If line 9 is 0 (the year is ending), the amount still to save is needed now. Look at payment plans and financial assistance.

Part C: Account checks

Health FSA election

My election is no more than the costs I can name that my FSA plan covers (eligible line 1 items plus line 2).
My election is no more than my plan's limit and the federal limit for the plan year ($3,400 for plan years beginning in 2026; check the IRS figure for 2027).
I know whether my plan has a carryover (up to $680 from plan years beginning in 2026) or a grace period of up to two and a half months, and the claims deadline.
I have kept the cushion (line 3) out of the FSA unless I am confident I will use it.

HSA contributions

I am eligible for each month I count, with no general-purpose FSA (mine or a spouse's) covering me, and not enrolled in Medicare.
My contributions plus my employer's stay within the yearly limit: for 2026, $4,400 self-only or $8,750 family; for 2027, $4,500 or $9,000; plus $1,000 if I am 55 or older.
If I am eligible for only part of the year, I prorated the limit by month or understand the last-month rule.
I keep every receipt for HSA withdrawals.
In California: I know the contributions and earnings count as state income.

Timing

I listed the month of each large cost. An HSA can pay only what has been deposited so far. An FSA pays up to the full election from the first day.

Optional: estimated tax value of pre-tax deposits

Pre-tax deposits × your combined tax rate. Use your own federal income tax rate, plus Social Security and Medicare if the deposit goes through payroll. Add your state rate only if your state gives the break; California does not for HSAs. Treat the result as a rough estimate.

Worked examples (fictional)

Example (fictional) 1: an FSA for predictable costs. A single worker paid every two weeks (26 paychecks) has a plan with a $4,000 out-of-pocket maximum.

Line 1: glasses $250 + fillings $300 = $550
Line 2: $15 prescription × 12 = $180, plus 4 specialist copays × $40 = $160, total $340
Line 3: cushion $500
Line 4: smaller of $840 and $4,000 = $840
Line 5: $550 + $840 = $1,390
Lines 6 and 7: $0
Line 8: $1,390
Line 10: $1,390 ÷ 26 = $53.46, rounded up to $54

FSA check: the costs she can name total $550 + $340 = $890, under the 2026 limit. She elects $890, about $34.23 a paycheck. The $500 cushion, about $19.23 a paycheck, goes to ordinary savings so it cannot be forfeited. Optional tax line: if her combined rate were 20 percent, the FSA would be worth about $890 × 0.20 = $178.

Example (fictional) 2: an HSA with an employer deposit. A worker on a self-only HSA-eligible plan has a $3,000 deductible and a $6,000 out-of-pocket maximum. She budgets by month, 12 months.

Line 1: dental work $400
Line 2: $60 prescription × 12 = $720, plus 2 visits × $150 = $300, total $1,020
Line 3: cushion = deductible, $3,000
Line 4: smaller of $4,020 and $6,000 = $4,020
Line 5: $400 + $4,020 = $4,420
Line 6: HSA balance $1,200
Line 7: employer deposit $600
Line 8: $4,420 − $1,200 − $600 = $2,620
Line 10: $2,620 ÷ 12 = $218.33, rounded up to $219

HSA check: her $2,620 plus her employer's $600 is $3,220, under the 2026 self-only limit of $4,400. In California, the $3,220 still counts as state income.

Example (fictional) 3: a family that reaches the cap. A family starts the sheet in March, with 10 months left in a calendar-year plan and nothing yet paid toward this year's $10,000 in-network family out-of-pocket maximum. A planned surgery in the third month will cost them $8,000.

Line 1: braces payments $1,500 + glasses $300 = $1,800
Line 2: surgery $8,000 + $100 prescriptions × 10 months = $1,000, total $9,000
Line 3: cushion $3,000
Line 4: smaller of $12,000 and $10,000 = $10,000 (the cap applies)
Line 5: $1,800 + $10,000 = $11,800
Line 6: savings $2,000
Line 7: $0
Line 8: $11,800 − $2,000 = $9,800
Line 10: $9,800 ÷ 10 = $980

Timing check: by the end of month 3 they will have $2,000 + (3 × $980) = $4,940, which is $3,060 short of the $8,000 surgery bill. Their options include asking the hospital for a payment plan or financial assistance, or using an FSA if one is offered, because an FSA pays up to the full election from the start. With an HSA, they could also pay the bill over time and reimburse themselves from the HSA as deposits build, as long as the HSA was open before the surgery.

Limitations

This is a budgeting aid, not a tax calculation. It does not decide whether you are HSA-eligible or which expenses your plan covers.
Estimates are only as good as what you enter. Prices, plan rules and limits change each year.
FSA plans can be narrower than IRS rules, and each employer sets its own deadlines and deposit schedules.
California and federal tax treatment of HSAs differ. A tax professional can help with your own return.

Sources

Revenue Procedure 2025-19: 2026 inflation-adjusted amounts for HSAs — Internal Revenue Service, accessed October 21, 2026.
Revenue Procedure 2026-24: 2027 inflation-adjusted amounts for HSAs — Internal Revenue Service, accessed October 21, 2026.
Revenue Procedure 2025-32: 2026 inflation adjustments, including the health FSA limit and carryover — Internal Revenue Service, accessed October 21, 2026.
Publication 969 (2025), Health Savings Accounts and Other Tax-Favored Health Plans — Internal Revenue Service, accessed October 21, 2026.
Publication 502 (2025), Medical and Dental Expenses — Internal Revenue Service, accessed October 21, 2026.
2025 Instructions for Schedule CA (540) — California Franchise Tax Board, accessed October 21, 2026.