Federal employment runs on milestones. Your leave accrual rate, your TSP vesting, your FERS vesting, your career tenure, your retention standing in a reduction in force, and your ability to carry benefits into retirement all depend on one question: how many years of creditable federal service have you completed? For most new hires, nobody explains this. The milestones arrive quietly, most employees only find out they have missed one when they need it.
This guide maps every major federal benefits milestone from your first day through year ten. The numbers come directly from the Office of Personnel Management, the Thrift Savings Plan, and Title 5 of the Code of Federal Regulations. If you want the short version: the four inflection points that matter most are 1 year (probationary period ends, MSPB appeal rights begin), 3 years (TSP agency contributions vest, leave accrual bumps to 6 hours, career tenure achieved), 5 years (FERS pension vests, health benefits participation clock starts for retirement eligibility), and 10 years (MRA+10 retirement becomes available, and FEHB/FEGLI retirement carryover unlocks for most).
Federal benefits are built on a compounding schedule. Small milestones in your first decade of service determine whether you can carry health insurance into retirement, whether your pension survives a voluntary separation, and whether you can be fired without appeal. Know your Service Computation Date — it runs the whole machine.
Section I The 1-year milestone: from probationary to protected
The first twelve months of your federal career are a probationary period. For most competitive service hires, the probationary period is exactly one year. During that window, your employment protections are minimal — an agency can terminate you with little process, written notice, and an effective date as short as "today." The Merit Systems Protection Board will not hear most probationary termination appeals unless the action was based on political affiliation, marital status, or a prohibited personnel practice.
Completing one year of current continuous service under a non-temporary appointment flips a switch. You move from "probationer" to "employee" as defined in 5 U.S.C. § 7511, which unlocks the full package of due process rights: advance written notice, an opportunity to respond, evidence against you, and — critically — the right to file an appeal with the MSPB within 30 days of an adverse action.
Your benefits start clock begins
You are automatically enrolled in FERS, start accruing annual and sick leave, and under rules effective October 2020 are automatically enrolled in the TSP at 5% of basic pay. The 1% Agency Automatic TSP contribution starts immediately, though it remains unvested until year 3.
Probationary period (competitive service)
Limited appeal rights. Termination requires only written notice and an effective date. Preference-eligible veterans in the excepted service may gain MSPB appeal rights after one year; non-preference excepted service employees typically need two years.
Probationary period ends · Full MSPB appeal rights
You become an "employee" under 5 U.S.C. § 7511 with the right to appeal suspensions over 14 days, removals, demotions, furloughs, and performance-based actions to the MSPB. This is the single largest jump in employment protection in your career.
What the 1-year mark actually buys you
After one year of continuous service, an agency can no longer fire you by handing you a one-page notice. Any adverse action of significance must follow the process in 5 CFR Part 752 — proposed action, 30-day advance notice, opportunity to reply, and a written decision that can be appealed. Your standing in reductions in force also improves: you move out of the lowest retention group.
Section II The 3-year milestone: vesting, tenure, and a 50% raise in leave
Year three is the most consequential stop on the federal milestone map, and the one most employees fail to track. Three separate benefits vest or improve on the same anniversary, and each one is worth real money over the course of a career.
TSP Agency Automatic (1%) contributions vest
From day one, your agency contributes 1% of your basic pay to your TSP account whether you contribute a penny yourself or not. That contribution is not yours until you complete three years of civilian service. If you leave federal service before year three, the Agency Automatic 1% and all its earnings are forfeited back to the TSP. Note that you are always immediately vested in your own contributions and in the agency matching contributions (up to 4% when you contribute 5%) from day one. Only the 1% Automatic is subject to the 3-year cliff.
For a GS-12 step 5 earning roughly $110,000 in 2026, three years of the Agency Automatic 1% plus growth is worth approximately $3,500 to $4,200 — money that disappears if you separate at year 2 years 11 months and 29 days.
Annual leave accrual jumps from 4 to 6 hours
Your annual leave accrual rate is tied directly to years of creditable service. At 3 years, it jumps from 4 hours per pay period to 6 hours per pay period — a 50% increase. Over a 26-pay-period year, that is the difference between 104 hours (13 days) and 160 hours (20 days) of annual leave. At a GS-12 rate, the additional 56 hours is worth roughly $3,000 per year in leave value, every year, for the next twelve years until the 15-year bump.
Career tenure
After approximately 3 years of substantially continuous creditable civilian service, competitive service employees achieve career tenure, converting their status from career-conditional to career. Career tenure does not change your day-to-day job, but it improves your retention standing in a reduction in force and makes it significantly easier to return to federal service after a voluntary break. Check box 24 of your SF-50 — career tenure shows as tenure code "1."
The three-year mark is the single largest compounding benefit jump of your federal career. Leave, TSP vesting, and career tenure all hit in the same window — and none of them trigger a notification. Watch your Service Computation Date.
Section III The 5-year milestone: FERS vests and the FEHB clock begins
Five years of creditable civilian service is the threshold at which the FERS basic annuity vests. Before year 5, if you leave federal service, your only retirement-related option is a lump-sum refund of your own contributions — you forfeit all claim to the pension benefit. After year 5, you have options even if you separate.
Deferred retirement becomes available
A vested employee who leaves before reaching their Minimum Retirement Age can defer receiving the FERS annuity until they reach age 62 (for employees with less than 20 years of service) or earlier under certain conditions. The annuity will be calculated using your high-3 at separation — not adjusted for inflation — which means a deferred retirement annuity is typically modest, but it is real money for someone who completes five years and moves on.
The 5-year FEHB participation clock begins
To carry your FEHB enrollment into retirement, you must be enrolled in FEHB (or covered as a family member) for the five years of service immediately before retirement. The five-year clock is separate from vesting — it is a participation clock. If you decline FEHB in your first years to save money and plan to enroll later, you are delaying your retirement eligibility for health coverage by the same amount of time. This is one of the most expensive optimization mistakes in federal benefits.
TSP catch-up planning becomes relevant
At 5 years, most employees have enough tenure and earnings history to run a realistic TSP projection to age 62. This is the milestone where contribution strategy conversations should shift from "am I hitting the 5% match" to "am I on track to replace my income at retirement." Use the TSP Projector in Pillar V to run the numbers.
Section IV The 10-year milestone: MRA+10, FEHB carryover, and the retirement runway
Ten years is the first serious retirement-eligibility milestone. It unlocks early retirement pathways and solidifies your ability to carry benefits into retirement. It also marks the moment when federal service has become a financial commitment significant enough to shape every career decision from that point forward.
MRA+10 retirement
With 10 years of creditable service and having reached your Minimum Retirement Age (between 55 and 57 depending on birth year), you become eligible for MRA+10 retirement. You can begin collecting a FERS annuity immediately, though it will be reduced by 5% for each year you are under age 62 unless you wait to postpone it. MRA+10 is rarely the optimal exit strategy, but it exists — and it exists only because of the 10-year threshold.
FEHB and FEGLI retirement carryover
At 10 years of service, combined with the 5-year FEHB participation requirement, most retiring federal employees can carry their FEHB and FEGLI coverage into retirement. This is not automatic — you must meet the participation clock and be retiring on an immediate annuity. But 10 years is the point where retiring with federal health coverage becomes a realistic plan rather than a theoretical one.
The pension math starts to matter
At 10 years and a high-3 salary around $120,000, your FERS basic annuity at immediate retirement would be approximately $12,000 per year (calculated as 1% × 10 years × $120,000). This is the moment where the compounding math of federal service starts to feel real: every additional year after this adds at least $1,200 annually to your eventual pension, for life. The same math is what makes staying to 20 years at age 62 so powerful — at that point, the multiplier jumps to 1.1% and the pension becomes substantial.
Section V Leave accrual across your career, visualized
Annual leave is the most visible benefit that scales with service years. Sick leave does not scale — it stays at 4 hours per pay period for your entire career. The chart below shows how annual leave accrual steps up at the 3-year and 15-year marks, along with the annual totals for each tier.
| Years of Service | Hours per Pay Period | Days per Year | Hours per Year |
|---|---|---|---|
| Less than 3 years | 4 hours | 13 days | 104 hours |
| 3 to 14 years | 6 hours (plus 10 hours in last pay period) | 20 days | 160 hours |
| 15 or more years | 8 hours | 26 days | 208 hours |
| SES, SL, ST (any service) | 8 hours | 26 days | 208 hours |
Section VI A worked example: the cost of leaving 2 months early
Jennifer leaves federal service at year 2, month 10
Jennifer is a GS-12 step 3 earning approximately $100,000 in locality-adjusted pay. She has been contributing 5% of her salary to TSP since her first day, capturing the full 5% agency match (1% automatic + 4% matching). She accepts a private sector offer and separates 2 months before her third anniversary.
What she keeps: All of her own TSP contributions. All agency matching contributions and their earnings (immediately vested). Her FERS contributions, refundable as a lump sum. She was not yet vested in FERS (5-year requirement), so she forfeits any pension claim.
What she loses: Three years of the Agency Automatic 1% TSP contributions (roughly $3,000 at her salary) plus all associated earnings. The 6-hour annual leave accrual rate she would have unlocked weeks later. Career tenure. Any FEHB continuation value she would have preserved with additional service.
The math changes entirely if Jennifer waits until month 36. The Agency Automatic 1% and its earnings vest and remain in her TSP account. Her leave accrual rate is permanently established on her Service Computation Date, meaning if she ever returns to federal service, she returns at the higher rate. And her career tenure status permanently improves her retention in any future RIF.
The four milestones that matter most
- Year 1 — Probationary period ends. MSPB appeal rights begin. Your employment protection jumps sharply, and adverse actions must follow full due process.
- Year 3 — TSP Agency Automatic 1% vests. Annual leave accrual jumps from 4 to 6 hours per pay period. Career tenure achieved. This is the biggest single compounding milestone of your career.
- Year 5 — FERS basic annuity vests. The 5-year FEHB participation clock toward retirement eligibility begins counting down in earnest.
- Year 10 — MRA+10 retirement becomes available. FEHB and FEGLI retirement carryover becomes realistic. The compounding math of federal service starts to dominate career decisions.
Section VII Frequently asked questions
You are vested in the FERS basic annuity after completing 5 years of creditable civilian service. Before 5 years, you can only receive a refund of your own contributions — not the agency contributions or the pension benefit itself. At 5 years, you can either take a refund or leave your contributions in place for a future deferred retirement annuity.
Most FERS employees vest in the 1% Agency Automatic TSP contribution after 3 years of civilian service. Certain positions — non-career SES, Executive Level positions, Members of Congress, and Congressional employees — vest after 2 years. You are always immediately vested in your own contributions and in the matching contributions (up to 4%) from day one. Only the 1% Automatic is subject to the vesting cliff.
If you die in service, you are automatically deemed 100% vested in all funds in your TSP account regardless of years of service.
Annual leave accrual jumps from 4 hours per pay period to 6 hours per pay period at 3 years of creditable service. It jumps again from 6 hours to 8 hours per pay period at 15 years of service. The rate change takes effect at the start of the first full pay period after you cross the threshold. Sick leave accrual stays at 4 hours per pay period for your entire career regardless of service years.
Career tenure is achieved after approximately 3 years of substantially continuous creditable civilian service. It converts your status from career-conditional (tenure code 2) to career (tenure code 1). The change does not affect your day-to-day job, but it improves your standing in reduction-in-force retention calculations and makes it significantly easier to return to federal service after a voluntary break.
You can verify your tenure status in box 24 of your SF-50 Notification of Personnel Action.
At 10 years of creditable service, you qualify for MRA+10 retirement (an early retirement pathway available once you reach your Minimum Retirement Age), you become eligible to carry FEHB and FEGLI into retirement if you meet the 5-year participation requirement, and your pension begins to represent meaningful replacement income. It is also the point where compounding makes staying to age 62 with 20 years of service dramatically more attractive, because the FERS multiplier jumps from 1.0% to 1.1% per year at that point.
It depends on the benefit. For annual leave accrual purposes, honorable active duty military service is automatically credited — you do not need to make any payment. For FERS retirement credit, military service only counts if you make a military service deposit (the "buyback"). For TSP vesting, only active duty performed under USERRA reemployment rights counts; prior military service before your federal civilian appointment generally does not count toward TSP vesting unless you were reemployed under USERRA.
See our dedicated guide on Military Service Buyback for the complete breakdown.
Your Service Computation Date (SCD) is the date that marks the start of your creditable federal service for a specific purpose. Most employees have several SCDs — one for leave accrual, one for retirement, one for reduction in force, and one for TSP vesting. These dates can differ if you have prior military service or gaps in federal employment. Your leave SCD drives when you hit the 3-year and 15-year accrual milestones.
Check your SCD in the employee data section of your SF-50. If the dates look wrong, contact your HR office immediately — errors in your SCD can cost you money for decades.