Sleeper has become the go-to platform for fantasy football — and increasingly for basketball and hockey too. It's free, the app is excellent, and the community features (chat, polls, trash talk) make it genuinely fun to use. But when it comes to keeper leagues, Sleeper takes a different approach than most commissioners expect.
This guide covers how Sleeper handles keepers, the manual steps commissioners need to know, and how to automate keeper eligibility analysis for your Sleeper league.
How Sleeper Handles Keeper Leagues
Here's the thing about Sleeper keeper leagues that surprises a lot of first-time commissioners: Sleeper doesn't have a dedicated "keeper mode" with automatic eligibility tracking. Instead, it gives commissioners manual tools to implement keepers however they want.
The process works like this:
- Each team decides who they want to keep (usually communicated via league chat or a poll)
- The commissioner goes into the draft board before the draft
- For each keeper, the commissioner manually assigns that player to the team's draft pick in the appropriate round
- When the draft starts, kept players are already on the board and those picks are used up
This approach is flexible — you can implement virtually any keeper rule system — but it puts all the work on the commissioner.
The Commissioner's Manual Keeper Workflow
If you're a Sleeper commissioner running a keeper league, here's the step-by-step process you'll go through every year:
1. Collect Keeper Selections
Sleeper doesn't have a built-in keeper selection form. Most commissioners use one of these methods:
- League chat: Ask everyone to post their keepers by a deadline
- Polls: Use Sleeper's poll feature for each team
- Google Form: Create an external form and share the link
- DMs: Have each manager DM their keepers privately
2. Verify Eligibility
This is the hard part. You need to check each keeper selection against your league's rules:
- Was the player on the team's roster at season end?
- What round were they originally drafted? (Check last year's draft board)
- How many years have they been kept? (Check your records from previous seasons)
- Were they acquired via trade or waivers? Does that affect their keeper cost?
- Are they within any keeper limits (max keepers per team, max years, etc.)?
Sleeper retains player notes and transaction history from year to year, which helps. But the platform doesn't calculate keeper eligibility for you — that's on the commissioner.
3. Set Keepers on the Draft Board
Once selections are verified:
- Open the draft room in Sleeper (go to your league → Draft)
- Click on the draft pick where the keeper should go (e.g., Team A's 3rd round pick)
- Select "Set Player" and choose the keeper
- Repeat for every keeper across all teams
For a 12-team league with 3 keepers each, that's 36 manual assignments. Doable, but tedious — and one wrong click means fixing it during draft night.
What Sleeper Does Well for Keepers
Despite the manual process, Sleeper has some genuine advantages for keeper leagues:
- Transaction history persists: All trades, waiver moves, and roster changes are saved year-over-year. This is invaluable for tracking acquisition history.
- Player notes: Commissioners can add notes to players that carry across seasons — perfect for tracking keeper years or special rules.
- Draft pick trading: Sleeper handles future draft pick trades natively. Traded picks show up correctly on the draft board.
- Free: No premium tier needed for keeper features. Everything is included.
- Great mobile app: The draft experience on mobile is smooth, which matters since many league members draft from their phones.
What Sleeper Doesn't Do
- No automatic keeper cost calculation: You need to manually determine each player's keeper round cost.
- No keeper year tracking: Sleeper doesn't know how many years a player has been kept. The commissioner tracks this externally.
- No keeper eligibility engine: There's no "show me who's keeper-eligible" button. It's all manual verification.
- No keeper selection deadline enforcement: The commissioner sets and enforces deadlines through communication, not platform settings.
Finding Your Sleeper Username and League
For external tools like KeeperTracker, you just need your Sleeper username — not a league ID. Here's why: Sleeper's API lets you look up all leagues associated with a username, so you can pick which league to analyze after entering your name.
Your Sleeper username is the one you chose when you created your account. You can find it in the app under Settings → Account. It's the @handle shown on your profile.
Automating Sleeper Keeper Analysis
KeeperTracker connects directly to Sleeper's API to pull your league data — rosters, draft history, and transactions — and runs keeper eligibility analysis automatically.
The process:
- Enter your Sleeper username on KeeperTracker
- Select your league from the list
- Get a full breakdown of every team's keeper-eligible players with draft round costs, acquisition method, and years on roster
This replaces the manual eligibility verification step. Instead of cross-referencing draft boards and transaction logs, you get an instant report that the commissioner can share with the whole league.
KeeperTracker works with Sleeper leagues for NFL, NBA, and NHL. Note: Sleeper does not currently offer MLB leagues, so baseball keepers on Sleeper aren't available.
Tips for Running a Smooth Sleeper Keeper League
- Use player notes religiously: After each season, add notes to kept players with their keeper year count and cost. Future you will be grateful.
- Keep a shared Google Sheet as backup: Even with KeeperTracker, having a shared spreadsheet with keeper history gives the league transparency and a backup record.
- Set deadlines early and loudly: Since Sleeper doesn't enforce keeper deadlines, over-communicate. Pin a message in the league chat with the deadline at least 3 weeks before the draft.
- Practice the draft board setup: If it's your first year, create a mock draft and practice assigning keepers before doing it live. It's easy once you've done it, but stressful the first time.
- Consider a keeper declaration channel: Create a dedicated channel in Sleeper for keeper declarations so they don't get buried in general chat.
Should You Use Sleeper for Your Keeper League?
Yes, if: Your league values a great app experience, free pricing, strong community features, and you have an organized commissioner who doesn't mind the manual keeper process.
Maybe not, if: Your league has complex keeper rules (salary caps, contracts, position-based limits) and you want the platform to enforce them automatically. In that case, Fantrax is the better fit.
For most fantasy football keeper leagues, Sleeper hits the sweet spot — especially when paired with KeeperTracker to handle the eligibility analysis that Sleeper leaves to the commissioner. Enter your username and get your keeper report in seconds.