The Core Rules That Work

Core 403(b) rules of thumb for 2025 — and when to ignore them

Rule of ThumbThe Simple VersionWhen It Breaks Down
Save 10–15% including matchTotal employer + employee = at least 10%Starting after 40 — need 15–20%
1× salary saved by 30Balance should equal annual salary at 30High-debt or late-start situations
10× salary saved at retirement$70K salary = $700K at retirement targetPension income reduces this need
110 minus age = stock %Age 40: 70% stocks, 30% bondsPension holders can be more aggressive
4% safe withdrawal rateWithdraw 4% of balance annually30+ year retirements may need 3.3%
Always capture the full matchNever contribute less than match thresholdHigh-fee plans may justify IRA instead

The 15% Rule: Most Versatile Starting Point

The 15% total savings rate (employee + employer contributions combined) is the most research-backed starting point for retirement. On a $72,000 salary with a 3% match, 15% total means contributing 12% yourself — $8,640/year. Over 30 years at 7%, that produces $816,000 — sufficient for most moderate retirement lifestyles.

💡Count the Match in Your 15%

If your employer matches 3%, you only need to contribute 12% personally to hit the 15% total rule. On $72,000, that is $8,640 — or $720/month from your paycheck.

The Benchmark Rules by Age

Fidelity-derived savings benchmarks by age — all retirement accounts combined

AgeBalance Benchmark (× salary)Example: $65K SalaryOn Track If...
30$65,000$50,000–$80,000
35$130,000$100,000–$160,000
40$195,000$150,000–$240,000
50$390,000$300,000–$480,000
60$520,000$400,000–$640,000
6510×$650,000$500,000–$800,000

When the Rules Break Down

Rules of thumb fail most often when: you have a pension (dramatically reduces required savings), you started very late (need higher rates), you plan to retire early (need bigger buffer), or your spending in retirement will differ significantly from your current lifestyle. A teacher with a $35,000 annual pension needs far less in her 403(b) than someone without one.

The 1% More Rule

The simplest and most actionable rule: increase your contribution by 1% each time you get a raise. This single habit, applied consistently, takes a 5% contributor to 12% in seven years — all without a significant lifestyle change. On $70,000, 1% more is $58/month before taxes — roughly the cost of two dinners out.

Check Your Numbers Against the Rules of Thumb

Enter your salary and current balance to see whether you are on track by the standard benchmarks.

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