Updated November 5, 2026. Quick answer: Worksheet 1 in Publication 571 finds your 403(b) maximum amount contributable (MAC): Part I is the limit on annual additions, Part II is the limit on elective deferrals with the 15-year increase, and Part III picks the MAC. With elective deferrals only, the MAC is the lesser of line 3 and line 17; age 50 catch-up contributions are not counted against it.
What the MAC is
The worksheet chapter opens with “Generally, your MAC is the lesser of your:” the limit on annual additions (chapter 3) and the limit on elective deferrals (chapter 4). Which limits you need depends on what went into the account: “If the only contributions made to your 403(b) account during the year were elective deferrals made under a salary reduction agreement, you will need to figure both of the limits. Your MAC is the lesser of the two limits.” “If the only contributions made to your 403(b) account during the year were nonelective contributions (employer contributions not made under a salary reduction agreement), you will only need to figure the limit on annual additions. Your MAC is the limit on annual additions.”
The inputs come from the earlier worksheets: includible compensation is Worksheet B. The yearly dollar limits are summarized on the 403(b) contribution limit page.
Part I: the limit on annual additions (lines 1 to 3)
| Line | What it asks |
|---|---|
| 1 | “Enter your includible compensation for your most recent year of service” |
| 2 | Maximum: “For 2025, enter $70,000.” “For 2026, enter $72,000” |
| 3 | “Enter the lesser of line 1 or line 2. This is your limit on annual additions” |
The worksheet then says “If you had only nonelective contributions, skip Part II and enter the amount from line 3 on line 18.” A footnote warns that “If you participate in a 403(b) plan and a qualified plan, you must combine contributions made to your 403(b) account with contributions to a qualified plan and simplified employee pension plans of all corporations, partnerships, and sole proprietorships in which you have more than 50% control.”
Part II: the limit on elective deferrals (lines 4 to 17)
| Line | What it asks |
|---|---|
| 4 | Maximum contribution: “For 2025, enter $23,500.” “For 2026, enter $24,500” |
| 5 | “Amount per year of service” (printed on the form as $5,000) |
| 6 | “Enter your years of service” |
| 7 | “Multiply line 5 by line 6” |
| 8 | “Enter the total of all elective deferrals made for you by the qualifying organization for prior years” |
| 9 | “Subtract line 8 from line 7. If zero or less, enter zero (-0-)” |
| 10 | “Maximum increase in limit for long service” (printed on the form as $15,000) |
| 11 | “Enter the total of additional pre-tax elective deferrals made in prior years under the 15-year rule” |
| 12 | “Enter the aggregate amount of all designated Roth contributions permitted for prior years under the 15-year rule” |
| 13 | “Add line 11 and line 12” |
| 14 | “Subtract line 13 from line 10” |
| 15 | “Maximum additional contributions” (printed on the form as $3,000) |
| 16 | “Enter the least of line 9, line 14, or line 15. This is your increase in the limit for long service” |
| 17 | “Add lines 4 and 16. This is your limit on elective deferrals” |
The note above line 5 says “If you have at least 15 years of service with a qualifying organization, complete lines 5 through 17. If not, enter zero (-0-) on line 16 and go to line 17.”
The 15-year rule behind lines 5 to 16
The chapter 4 text is “If you have at least 15 years of service with an educational organization (such as a public or private school), hospital, home health service agency, health and welfare service agency, church, or convention or association of churches (or associated organization) and it is allowed by the terms of the plan document, the limit on elective deferrals to your 403(b) account is increased by the least of:” the $3,000 figure, “$15,000, reduced by the sum of:” the earlier additional pre-tax and Roth amounts, or “$5,000 times the number of your years of service for the organization, minus the total elective deferrals made by your employer on your behalf for earlier years.” The result is stated as “your elective deferrals under this limit can be as high as $26,500 for 2025 and $27,500 for 2026.”
How years of service are counted (full-time, part-time, fractions of a year) is the subject of chapter 4 of the publication. One rule worth knowing: “Note: You can’t accumulate more than 1 year of service in a 12-month period.”
Part III: line 18, your MAC
| Line | What it asks |
|---|---|
| 18 | “If you had only nonelective contributions, enter the amount from line 3. This is your MAC.” |
| 18 | “If you had only elective deferrals, enter the lesser of line 3 or line 17. This is your MAC.” |
| 18 | “If you had both elective deferrals and nonelective contributions, enter the amount from line 3. This is your MAC. (Use the amount on line 17 to determine if you have excess elective deferrals as explained in chapter 7.)” |
Catch-up contributions sit outside the MAC: “Catch-up contributions aren’t counted against your MAC.” “Therefore, the maximum amount that you are allowed to have contributed to your 403(b) account is your MAC plus your allowable catch-up contributions.” The publication also has a Worksheet C for the age 50 and age 60 to 63 limits, but the January 2026 edition prints a placeholder where the age 50 dollar amount belongs, on line 1 of the worksheet and in chapter 6, so this page does not walk through it. The current age 50 figure is on the 401(k) catch-up page.
A discrepancy in the publication’s own example
The example for Max says “Max determines the limit on annual additions for 2026 to be $72,000, the lesser of the includible compensation, $70,475 (Table 3-4), and the maximum amount of $72,000.” Under line 3 of the worksheet, “Enter the lesser of line 1 or line 2.” Of $70,475 and $72,000 the lesser is $70,475 (computed), not $72,000, and the printed Table 4-2 shows $72,000 on line 3. Max’s MAC is not affected, because Max has only elective deferrals and the publication correctly takes “the maximum amount that can be contributed to a 403(b) account on Max’s behalf in 2026 is $24,500, the lesser of both limits.” If your includible compensation is below the line 2 maximum, follow the line 3 instruction as printed, not the example’s table.
Examples with invented numbers
Illustration, not an IRS example. All four are computed from the inputs shown, using the 2026 maximums on lines 2 and 4. Each assumes the plan allows the 15-year increase where it is used.
Case 1 (computed), elective deferrals only, $80,000 of includible compensation and under 15 years of service:
| Line | Entry | Value |
|---|---|---|
| 1 | Includible compensation for the most recent year of service (invented) | $80,000 |
| 2 | Maximum for 2026 | $72,000 |
| 3 | The lesser of line 1 or line 2 (computed) | $72,000 |
| 4 | Maximum contribution for 2026 | $24,500 |
| 16 | Under 15 years of service, enter zero | -0- |
| 17 | Line 4 plus line 16 (computed) | $24,500 |
| 18 | The lesser of line 3 or line 17 (computed) | $24,500 |
The MAC is $24,500 (computed): the elective deferral limit is below the annual additions limit.
Case 2, the 15-year rule at work: twenty years of service, $60,000 of prior elective deferrals, $4,000 of prior additional pre-tax deferrals and $1,000 of prior Roth amounts under the rule, on the same $80,000 of includible compensation.
| Line | Entry | Value |
|---|---|---|
| 4 | Maximum contribution for 2026 | $24,500 |
| 5 | Amount per year of service | $5,000 |
| 6 | Years of service (invented) | 20 |
| 7 | Line 5 times line 6 (computed) | $100,000 |
| 8 | Elective deferrals made by the organization for prior years (invented) | $60,000 |
| 9 | Line 7 minus line 8, not below zero (computed) | $40,000 |
| 10 | Maximum increase in limit for long service | $15,000 |
| 11 | Additional pre-tax deferrals made in prior years under the 15-year rule (invented) | $4,000 |
| 12 | Designated Roth contributions permitted for prior years under the 15-year rule (invented) | $1,000 |
| 13 | Line 11 plus line 12 (computed) | $5,000 |
| 14 | Line 10 minus line 13 (computed) | $10,000 |
| 15 | Maximum additional contributions | $3,000 |
| 16 | The least of line 9, line 14 or line 15 (computed) | $3,000 |
| 17 | Line 4 plus line 16 (computed) | $27,500 |
The increase is $3,000 and line 17 is $27,500 (computed), the same $27,500 the publication gives as the 2026 high end. The MAC is $27,500, the lesser of $72,000 and $27,500 (computed).
Case 3, low pay: only $20,000 of includible compensation, elective deferrals only. Line 3 is $20,000 and line 17 is $24,500 (computed), so the MAC is $20,000: the annual additions limit is the lower one, and 100% of includible compensation is the cap.
Case 4 (computed), almost used up: sixteen years of service, $78,500 of prior elective deferrals and no earlier use of the rule, on $80,000 of includible compensation.
| Line | Entry | Value |
|---|---|---|
| 4 | Maximum contribution for 2026 | $24,500 |
| 5 | Amount per year of service | $5,000 |
| 6 | Years of service (invented) | 16 |
| 7 | Line 5 times line 6 (computed) | $80,000 |
| 8 | Elective deferrals made by the organization for prior years (invented) | $78,500 |
| 9 | Line 7 minus line 8, not below zero (computed) | $1,500 |
| 10 | Maximum increase in limit for long service | $15,000 |
| 11 | Additional pre-tax deferrals made in prior years under the 15-year rule (invented) | $0 |
| 12 | Designated Roth contributions permitted for prior years under the 15-year rule (invented) | $0 |
| 13 | Line 11 plus line 12 (computed) | $0 |
| 14 | Line 10 minus line 13 (computed) | $15,000 |
| 15 | Maximum additional contributions | $3,000 |
| 16 | The least of line 9, line 14 or line 15 (computed) | $1,500 |
| 17 | Line 4 plus line 16 (computed) | $26,000 |
Line 9 is only $1,500 (computed), so line 16 is $1,500, line 17 is $26,000 (computed) and the MAC is $26,000 (computed).
Edition
This page reads Publication 571 (Rev. January 2026), Tax-Sheltered Annuity Plans (403(b) Plans), the file irs.gov served on 2026-11-05. Worksheet titles, line numbers and dollar amounts belong to that edition, so check the label printed on the worksheet in your own copy before you follow a line reference. Chapter 4 carries Max’s example and Table 4-2, the filled-in worksheet.
Common mistakes
- Treating the 15-year increase as automatic. The text says it applies only if the plan document allows it.
- Entering the line 2 or line 4 maximum for the wrong year. The worksheet prints both the 2025 and the 2026 amount.
- Counting catch-up contributions inside the MAC. The publication says they aren’t counted against it.
- Using line 17 as the MAC when there were also nonelective contributions. The third bullet on line 18 uses line 3 and keeps line 17 only for the excess deferral test.
Related: Publication 571, the 403(b) contribution limit page, 457(b) special catch-up rules, and 403(b) versus 457(b).
Find the right next step for your situation
About how much do you have invested? Pick the range that fits; your next step appears immediately below.
Compare vetted advisors for your finances
For U.S. investors with $250,000 or more in investable assets. WiserAdvisor is an independent service matching you with 2 to 3 vetted advisers. Its form asks for your ZIP code and answers to a few questions; a match is not guaranteed.
Free to request, with no obligation to hire. By submitting, you consent to calls, texts and emails from WiserAdvisor and up to three advisers. Advisers pay for introductions.
Clear Money Guide may earn a referral payment for a qualifying completed form. An introduction is not a Clear Money Guide recommendation.
Opens on WiserAdvisor’s site in a new tab.
Explore optional adviser matching today
Considering financial advice? Request an adviser introduction with no obligation to hire.
The form is run by Kapitalwise, our advisor-matching partner. Requesting an introduction is free. Submitting the form shares your contact details with advisers, so expect calls and texts. Advisers pay for introductions. Clear Money Guide may earn a referral payment for a qualifying submitted form, whether or not you hire anyone. A match is not guaranteed.
The Kapitalwise form opens here; you stay on this page.
What happens when you press the button
It asks about nine questions: age, investable assets, location; then your name, email and phone number, and verifies the phone by text. Nothing loads and nothing reaches Kapitalwise until you press the button.
Prefer flat-fee or hourly pricing instead? Compare ranges here.
Answer againSources
- Publication 571 (Rev. January 2026), Tax-Sheltered Annuity Plans (403(b) Plans): https://www.irs.gov/pub/irs-pdf/p571.pdf
- IRS, About Publication 571, Tax-Sheltered Annuity Plans (403(b) Plans): https://www.irs.gov/forms-pubs/about-publication-571
Read from the IRS documents linked above on November 5, 2026. General information, not tax advice. Your own facts decide the outcome, and a preparer, the account provider or the IRS is the right place to confirm anything consequential.