Polymarket Over/Under Markets Guide
Last verified: 2026-06-27 PDT
Polymarket over/under markets turn a number into a prediction contract. The question might be about total games in a tennis match, a team score, a crypto price level, a CPI print, a box-office number, rainfall, temperature, or any event where the outcome can be compared with a line.
The simple version: over wins if the measured result is above the line, and under wins if it is below the line. The real version is more detailed. You need the exact threshold, the source, the deadline, the timezone, tie handling, cancellation handling, and the executable spread before the displayed probability means anything.
The Bucko approach is to treat every over/under market like a mini contract. Read the line first. Read the source second. Read the execution third.
Key definitions in plain English
- ▸Line: The number the outcome is measured against, such as 36.5 total games or a price threshold.
- ▸Over side: The contract side that resolves positively if the final measured result clears the line according to market wording.
- ▸Under side: The contract side that resolves positively if the final measured result stays below the line according to market wording.
- ▸Half-point line: A line like 36.5 that avoids an exact tie in integer-scored events.
- ▸Threshold market: A market that asks whether a number will hit, exceed, close above, or finish in a certain range.
- ▸Resolution source: The source named by the market for settlement.
- ▸Bid/ask spread: The gap between what buyers are bidding and sellers are asking.
What current market samples show
Polymarket Gamma API market samples checked on 2026-06-27 PDT surfaced active over/under-style questions, including tennis match-total examples with a listed official scoring source, total-game wording, retirement or non-completion language, and timing rules. These samples are topic research only. They are not trade ideas, outcome forecasts, or instructions.
The useful lesson is that over/under markets often look simple because the headline is short. The settlement logic is not short. A market titled around a total still needs answers to questions like: which event, what counts, what does not count, what source settles it, what happens if the event is delayed, and whether a tiebreak or revised data point counts.
The over/under checklist
Before logging a Polymarket over/under in Bucko, write down:
- ▸The exact market question.
- ▸The underlying event or data release.
- ▸The line or threshold.
- ▸Whether the wording says over, at least, greater than, hit, close above, or finish above.
- ▸The named resolution source.
- ▸The deadline and timezone.
- ▸What happens if the event is canceled, delayed, not completed, revised, or has missing data.
- ▸Best bid, best ask, spread, and visible depth.
- ▸Your maximum loss cap.
- ▸The post-resolution review note you will check later.
That list keeps the market from becoming a vibes trade. It turns the page into a structured research note.
Price-to-probability example
Suppose an over/under market displays the Over side near 0.54. A beginner might call that 54%. A better read separates displayed probability from executable price:
| Item | Example |
|---|---|
| Displayed Over price | 0.54 |
| Best Over ask | 0.57 |
| Best Over bid | 0.51 |
| Spread | 6 cents |
| Line | 36.5 total units |
| Source | copied from market wording |
| Max loss if buying 100 shares at 0.57 | $57 before fees/spread effects |
The difference between 0.54 and 0.57 matters. If your research says the fair probability is only slightly above the displayed number, the spread can erase the edge before anything happens. This is why Bucko pages emphasize execution quality, not just headline probability.
Common over/under market types
| Market type | What to verify |
|---|---|
| Sports totals | scoring source, overtime/tiebreak handling, postponement rule, and completion rule |
| Crypto thresholds | exchange or index source, timestamp, hit-vs-close wording, and timezone |
| Weather totals | station/source, measurement window, unit, revision handling, and local time |
| Macro data | release source, initial vs revised data, exact print, and publication time |
| Entertainment totals | box-office or chart source, region, time window, and data publication rules |
Never copy assumptions between markets. “Over 36.5” in tennis is not the same research problem as “Bitcoin above $X at midnight” or “CPI above X%.”
Common mistakes
- ▸Missing the verb. “Hit,” “close above,” “finish above,” and “at or above” can mean different things.
- ▸Ignoring source timing. The event may happen before the named source publishes the number.
- ▸Treating revisions casually. Some data markets may rely on an initial release, while others may specify another source path.
- ▸Forgetting spread. A displayed 54% market is not always executable at 54%.
- ▸Skipping cancellation language. Sports and event markets often need delay, retirement, cancellation, or 50-50 handling notes.
Where Bucko fits
Bucko is a research, journaling, scenario-analysis, guardrail, and review workspace. For over/under markets, use it to store the line, source, verb, timing, spread, visible depth, max-loss cap, update triggers, and final review. Bucko is not here to tell readers what to trade. It is here to make the process visible enough to audit.
Polymarket CTA
If you are eligible for the U.S. app offer, use code BUCKO for a $50 deposit bonus on the Polymarket US app: https://www.poly.market/BUCKO. Confirm the current app flow and eligibility before depositing.
Sources and last-verified notes
- ▸Polymarket docs checked 2026-06-27 PDT for market-data surfaces, CLOB/order-book concepts, and API access patterns.
- ▸Polymarket Gamma API samples checked 2026-06-27 PDT for active over/under-style market wording and source fields.
- ▸Use each market's own resolution wording first, then the official event, data, score, exchange, weather, or publication source named by that market.
- ▸User-provided Bucko/Polymarket partner offer: code BUCKO, $50 deposit bonus for eligible U.S. app downloads.