January Polymarket Pregame Favorite Accuracy

For January 2026, the pregame Polymarket moneyline favorite won 154 of 233 resolved games.

Summary

So the direct answer is:

• How accurate was Polymarket before the game in January?
  66.1% on games with a clear pregame favorite.

• How many times did the favorite actually win?
  154 times.

Here’s the daily win-rate view:

Key takeaways

• A 66.1% hit rate means Polymarket favorites were right about two out of every three games.
• The strongest daily result was January 26, when favorites went 7-0.
• The roughest days were January 8 and January 25, when favorites won only 33% of games.

Biggest upsets of the month

These were some of the most notable losses by heavily favored teams:

• Thunder lost to Hornets on 1/5 despite being around 89.5% favorites
• 76ers lost to Nuggets on 1/5 despite being around 87.5% favorites
• Rockets lost to Kings on 1/11 despite being around 85.5% favorites
• Timberwolves lost to Jazz on 1/20 despite being around 85.5% favorites
• Cavaliers lost to Jazz on 1/12 despite being around 82.5% favorites

Coverage note

• There were 2 unmatched games in the month, so they were excluded from the favorite-accuracy calculation:
  • Nuggets at Grizzlies on 1/25
  • Mavericks at Bucks on 1/25

If you want the deeper before-vs-after snapshot report next, I can break this into:

• pregame favorite probability buckets (60-70%, 70-80%, 80%+),
• home vs away favorite accuracy, and
• largest in-game probability swings from pregame to final outcome.

January vs February Polymarket Pregame Favorite Accuracy

Polymarket favorites were more accurate in February than in January.

Headline comparison

Change from January to February

So the clean takeaway is:

• January: favorites won 154 of 233 games
• February: favorites won 118 of 166 games
• February was better by about 5 percentage points

That means Polymarket’s pregame favorite was right a little over 7 out of 10 times in February, compared with about 2 out of 3 in January.

Here’s the month-to-month comparison visually:

February notes

• 118 favorites won
• 48 favorites lost
• No unmatched games
• February’s strongest upset risk still showed up in a few spots:
  • Pistons lost to the Wizards as about 89.5% favorites
  • Thunder lost to the Bucks as about 83.5% favorites
  • Knicks lost to the Pacers as about 80.5% favorites

What this suggests

February looked like a more stable month for chalk:

• fewer data gaps,
• a higher favorite hit rate,
• and fewer broad stretches where underdogs piled up wins.

If you want the sharper next cut, the best follow-up is to break both months into:

1. 60-70% favorites
2. 70-80% favorites
3. 80%+ favorites

That will show whether February improved because:

• medium favorites got home more often, or
• the heavy favorites were simply much safer.

December Through February Polymarket Pregame Favorite Accuracy

Across Dec. 1, 2025 through Feb. 28, 2026, the pregame Polymarket favorite won 327 of 493 matched games with a clear favorite.

Summary

So the headline answer is:

• How accurate was Polymarket before the game from Dec-Feb?
  66.3%

• How many times did the favorite actually win?
  327 times

Month-by-month comparison

Using the earlier January and February results alongside this combined Dec-Feb report:

What stands out

• December was the weakest month at just 58.5%
• January improved to 66.1%
• February was the strongest at 71.1%
• The combined Dec-Feb number lands near January because January had the biggest sample

Here’s the month-by-month view:

The trend is pretty clear: Polymarket favorites got steadily more accurate from December into February.

Notable upsets in the full Dec-Feb sample

Some of the biggest favorite misses in the span:

• Thunder lost to the Hornets on 1/5 as roughly 89.5% favorites
• Pistons lost to the Wizards on 2/5 as roughly 89.5% favorites
• 76ers lost to the Nuggets on 1/5 as roughly 87.5% favorites
• Spurs lost to the Jazz on 12/27 as roughly 85.5% favorites
• Rockets lost to the Kings on 1/11 as roughly 85.5% favorites

Data-quality note

The full Dec-Feb sample had 51 unmatched games, and almost all of that gap came from December. That matters because:

• January: only 2 unmatched games
• February: 0 unmatched games
• December: 49 unmatched games

So December’s number is useful, but it’s the least clean month of the three from a coverage standpoint.

Bottom line

If you treat Polymarket’s pregame favorite as a simple signal:

• It was solid overall from Dec-Feb at 66.3%
• It got meaningfully better as the season moved forward
• The strongest single month in this stretch was February
• The favorite won 327 times over the full period

If you want, I can next break Dec-Feb by probability bucket like:

• 50-59% favorites
• 60-69% favorites
• 70-79% favorites
• 80%+ favorites

That’s the best way to see whether the edge came mostly from heavy chalk or if medium favorites were also reliable.