WhamR
Both Teams to Score (BTTS): A Practical Guide
How BTTS probability is calculated and what makes both sides likely to find the net.
Both Teams to Score asks whether each side will score at least once. A 1–1 draw, a 3–2 thriller and a 4–1 rout all settle as "Yes". A 2–0 or a 0–0 settles as "No". It is independent of the result, which makes it a useful market when you have a view on attacking quality but not on who wins.
The calculation
BTTS Yes requires the home team to score and the away team to score. If you know each team's chance of failing to score (the zero-goal probability from a Poisson model), the calculation is:
P(BTTS Yes) = (1 − P(home scores 0)) × (1 − P(away scores 0))
With home expected goals of 1.6 and away of 1.1, the chances of blanking are 20.2% and 33.3%. BTTS Yes is therefore 79.8% × 66.7% ≈ 53.2%.
Balance matters more than volume
A match with 3.0 expected goals split 2.6 to 0.4 has a lower BTTS chance than a match with 2.6 expected goals split 1.3 to 1.3. The weaker attack is the limiting factor. In the lopsided case the away side blanks about 67% of the time, so BTTS Yes falls to roughly 31%. In the balanced case each side blanks about 27% of the time and BTTS Yes rises to about 53%.
Signals for BTTS Yes
- Both teams score regularly and concede regularly.
- Evenly matched sides with attacking managers.
- Defensive injuries or suspensions on either side.
Signals for BTTS No
- A dominant favourite facing a team that rarely scores away from home.
- One side with a strong clean-sheet record.
- Low-tempo matches with little at stake.
BTTS in a live match
If both teams have already scored, BTTS Yes is settled. If only one has scored, the question becomes whether the other side scores in the time remaining. A team expected to score 1.1 goals over 90 minutes is expected to score only around 0.37 in the final 30, giving roughly a 31% chance — so BTTS Yes can drift quickly as the clock runs.
Key takeaways
- BTTS depends on the weaker attack more than total goals.
- Multiply each team's chance of scoring at least once.
- In play, focus on the side that has not yet scored and the minutes left.