Estimate what college will cost by the time you get there, what that bill is worth in today's dollars, and the monthly saving that would cover it — or a chosen share of it — from the savings you already have.
Average annual U.S. college cost (2025–2026)
| Type | Annual cost |
|---|---|
| 4-year private | $65,470 |
| 4-year public (in-state) | $30,990 |
| 4-year public (out-of-state) | $50,920 |
| 2-year public | $21,320 |
Source: College Board, Trends in College Pricing and Student Aid 2025. These are estimated full-time undergraduate budgets, including categories beyond tuition and fees. They are sticker-budget averages, not the net price a particular student will pay after grants and scholarships.
How much will college cost in 18 years?
Starting with the $30,990 in-state public budget and four years of attendance, the increase-rate assumption changes the estimate substantially:
| Annual cost increase | Freshman year in 18 years | Four-year projected total |
|---|---|---|
| 3% | $52,758 | $220,721 |
| 5% | $74,581 | $321,454 |
| 7% | $104,744 | $465,058 |
The 5% row can be reproduced by entering $30,990, 18 years until college, four years of attendance, and a 5% cost increase. This sensitivity range is more useful than treating one compounded number as a prediction.
Use a school's net price rather than its sticker price when you have a specific college in mind. The U.S. Department of Education Net Price Calculator Center explains that net price subtracts grants and scholarships. An actual financial aid offer remains more specific than this planning estimate.
Examples
Default plan (in-state public, 3 years out)
Today's annual cost $30,990, rising 5%, four years of college starting in 3 years, 35% paid from savings, no current balance, 5% return taxed at 25%. Total college cost is $154,625 ($130,836 in today's money). Covering the full bill takes $1,773 per month for 7 years. The 35% savings share is $54,119 ($45,792 today), or $621 per month.
Newborn, 65% from a 529
Today's cost $28,840, 5% increases, four years starting in 19 years, 65% from savings, $10,000 already saved, 7% return and 0% tax (a 529). Total cost $314,110 ($78,373 today). After the $10,000 already saved, the full bill needs $499 per month for 23 years; the 65% share needs $299 per month, with $47,370 due freshman year.
In-state public college starting in 18 years
At $30,990 today and a 5% annual cost increase, the four modeled college years are $74,581, $78,310, $82,226, and $86,337. The projected total is $321,454. With a 5% return and 0% modeled tax drag, its present value is $123,960 and the equivalent contribution is $775 per month for 22 years.
Formula
Each college year is inflated, then discounted at the after-tax return
r = return × (1 − tax):
cost_k = today × (1 + g)^(start + k)
total cost = sum of cost_k
today's money (PV) = sum of cost_k / (1 + r)^(start + k)
monthly saving = PMT of (PV − current savings) over (start + N) years
at a monthly rate r / 12
g is the college-cost increase rate, start is years until freshman year, and
N is the number of years attended. A 529 plan uses tax = 0 so r equals the
stated return.
College Board 2025–2026 published student-budget averages are $65,470 private four-year, $30,990 in-state public, $50,920 out-of-state public, and $21,320 two-year public. Pick one to fill today's cost, or enter a net price from a specific school's calculator.
Assumptions and limits
- Cost increases and investment returns are constant in the model; actual tuition, aid, markets, and inflation vary from year to year.
- Monthly contributions continue through the modeled attendance period. Change the assumptions if you plan to finish funding before enrollment.
- The selected savings percentage does not predict grants, scholarships, or loan eligibility.
- A 0% modeled tax drag is not tax advice. IRS Publication 970 explains qualified tuition program expenses and distribution rules.
Compare saving now with borrowing later
If savings will not cover the projected cost, the Student Loan Calculator can model borrowing during school and later repayment. Use the Savings Calculator for a separate contribution-and-interest scenario. Keep grants, net price, loan terms, and uncertain investment returns distinct in the comparison.