Why MLB Home Teams Become Profitable After April
An MLB market timing case study
One of the most consistent mistakes sports betting markets make happens early in the season — before pricing fully stabilizes. Major League Baseball is a textbook example of this behavior.
From 2004 onward, betting markets have repeatedly mispriced home teams in April, then overcorrected in May, creating a narrow but measurable edge for bettors who understand when the market adjusts.
This article breaks down why that happens — and how bettors can take advantage of it.
The Data: April vs May in MLB
Home-field advantage exists in nearly every sport, but its pricing impact is not constant throughout the season.
Since 2004:
- April home teams
1692–1522 (52.6%)
–171.97 units, –4.0% ROI - May home teams
2135–1654 (56.3%)
+119.13 units, +2.4% ROI
April has been the worst month for blindly betting MLB home teams.
May has been the most profitable.
That difference is not random.
Why the Market Misses This
Early-season pricing suffers from three predictable issues:
- Recency bias
Bettors overweight small April samples and overreact to early streaks. - Incomplete information
Teams are not fully “defined” yet — rotations, bullpens, and roles are still stabilizing. - Bookmaker positioning
Sportsbooks price lines knowing bettors hesitate to back home teams that struggled in April — even when those teams are fundamentally sound.
By May, pricing starts to normalize — but not perfectly. That lag is where the edge exists.
This is a classic example of market timing, not team strength.
Narrowing the Edge: A Filtered System
Rather than betting every home team in May, applying logical filters improves efficiency:
System parameters:
- Home teams in May
- –175 or cheaper
- Total between 7 and 10
- Team scored 2+ runs in last game
- Team win % under .600
- Team win % lower than opponent
- Non-interleague games
- Short streaks only
- Opponent coming off a close game
Results:
476–333
+146.6 units, +15.6% ROI
This works because it removes:
- Blowout-prone mismatches
- Publicly inflated favorites
- Emotionally charged anomaly games
What remains are quietly mispriced spots.
What This Actually Demonstrates
This isn’t about “home teams being good.”
It demonstrates:
- Early-season mispricing
- Market correction timing
- Why when you bet matters more than what you bet
This is the same principle behind Closing Line Value — identifying moments where prices lag reality before the market fully adjusts.
👉 For a broader explanation of why beating the number matters more than winning individual bets, see:
Closing Line Value Explained
How to Use This Going Forward
You don’t need to blindly follow this system every season.
Use it as:
- A timing filter
- A confirmation signal
- A reminder that April results often lie
Markets don’t become efficient overnight — they drift.
The bettor’s job is to recognize when that drift creates opportuni
