Short answer
Different SCDs answer different questions.
A leave SCD usually answers how fast annual leave accrues. A retirement SCD answers what service counts for FERS eligibility and pension computation. OPM separates those rules, so the dates can differ even when the service history is correct.
Start here
What you actually came to find out
Plain answers first. Sources stay below for checking details.
What is the leave SCD?
It is the date agencies use to decide annual leave accrual. OPM says certain prior service can count for leave even when retirement credit is handled separately.
What is the retirement SCD?
It is the service-credit timeline used for FERS retirement eligibility and annuity computation. Military service and redeposits can change this line.
Why can they be different?
Prior service, temporary service, military service, deposits, redeposits, and breaks in service can count differently across leave and retirement rules.
Where does SF 3108 fit?
SF 3108 is the OPM service-credit payment form trail. It matters when a deposit or redeposit may add retirement credit.
Leave accrual
One date
OPM uses service credit rules to determine annual leave accrual rates.
Source trail: OPM
FERS retirement
Another date
OPM explains creditable service for FERS annuity eligibility and computation separately.
Source trail: OPM
Deposits
Can matter
OPM points employees to SF 3108 when applying to make a FERS service-credit payment.
Source trail: OPM
MRA math
Service + age
OPM retirement type rules use age and years of creditable service, not the leave-accrual date by itself.
Source trail: OPM
The useful move is to label the date before using it: leave accrual, retirement eligibility, pension computation, or service deposit.
Neutral landscape
The shape of the question
OPM leave guidance explains why a service date can affect annual leave accrual.
Source trail: OPM
OPM FERS creditable-service guidance explains which service can count for annuity eligibility and computation.
Source trail: OPM
OPM retirement-type guidance shows why the date only matters after it is paired with age and years of service.
Source trail: OPM
SF 3108 is the official paper trail when the question becomes a service-credit deposit or redeposit.
Source trail: OPM
Curator core
What the authorities say
These sources are here for the reader who wants to check the work. The plain-English answer stays above them.
Source 01
OPM
Service Credit for Leave Rate Accrual and Retirement
OPM explains how prior service can count for leave accrual and why leave service credit can differ from retirement service credit.
Source framing
OPM separates service that counts for leave accrual from service that counts for retirement.
Strongest for: official leave SCD and service-credit distinctions
Read at OPMSource 02
OPM
FERS Creditable Service
OPM explains FERS creditable civilian service, military service deposits, redeposits, and the service-credit payment process.
Source framing
OPM explains which service counts toward FERS annuity eligibility and computation.
Strongest for: official FERS retirement SCD and service-credit rules
Read at OPMSource 03
OPM
FERS Types of Retirement
OPM explains optional, early, deferred, disability, and MRA+10 retirement paths for FERS employees.
Source framing
OPM separates FERS retirement eligibility paths by age, service, and retirement type.
Strongest for: FERS retirement type and eligibility context
Read at OPMSource 04
OPM
SF 3108: Application to Make Service Credit Payment
SF 3108 is the OPM form used for FERS service-credit payment requests.
Source framing
OPM points FERS employees to SF 3108 when applying to make a service-credit payment.
Strongest for: official FERS service-credit deposit form trail
Read at OPMPlain-English forks
The forks people face
Most retirement questions hide a few smaller decisions. These are the practical pieces that change the plan.
Is the question leave accrual or retirement?
Why it matters: The same service period can be treated differently depending on which benefit is being measured.
In real life: This fork changes whether the date affects time off or pension math.
What to look at: What to look at: SF 50, agency HR record, OPM leave service-credit rules, and OPM FERS creditable-service rules.
Is there prior military or temporary service?
Why it matters: Those periods are often where the dates split.
In real life: This fork changes whether a payment or documentation step belongs in the map.
What to look at: What to look at: OPM creditable-service guidance and SF 3108 deposit instructions.
Is a retirement date close?
Why it matters: A small service-credit difference can affect eligibility, supplement assumptions, FEHB continuation, and pension computation.
In real life: This fork changes the date that belongs in the federal pension calculator.
What to look at: What to look at: OPM FERS retirement type rules.
Common questions
Quick answers
Short, plain answers for the questions people usually have next. The source trail stays available below.
Is leave SCD the same as retirement SCD?+
Not always. OPM separates leave service-credit rules from FERS retirement creditable-service rules, so the dates can differ.
Does an earlier leave SCD mean an earlier retirement?+
Not by itself. FERS retirement eligibility depends on creditable service and age under OPM retirement-type rules.
What form is used for a FERS service-credit payment?+
OPM uses SF 3108 for FERS service-credit payment requests.
How this page is curated
This page uses OPM leave service-credit guidance, OPM FERS creditable-service guidance, OPM retirement-type rules, and SF 3108. It separates date labels before discussing retirement math.
Read the planner methodologyTrust anchor
Sources used on this page
Every source named above is listed here in one place.
OPM. Service Credit for Leave Rate Accrual and Retirement
https://www.opm.gov/policy-data-oversight/pay-leave/leave-administration/fact-sheets/service-credit/OPM. FERS Creditable Service
https://www.opm.gov/retirement-center/fers-information/creditable-service/OPM. FERS Types of Retirement
https://www.opm.gov/retirement-center/fers-information/types-of-retirement/OPM. SF 3108: Application to Make Service Credit Payment
https://www.opm.gov/forms/pdf_fill/sf3108.pdf
Before you act on this
This plan is educational. It is not personalized financial, tax, or insurance advice. Projections illustrate the math, they do not predict the future. Talk to your own licensed financial professional before acting on any of it.