Teaser EV: When Buying Points Is Worth It

What Is a Teaser?

A teaser lets you move the spread in your favor on two or more legs in exchange for reduced payout odds. Buy 6 points on a 2-team NFL teaser and the book might pay -120 instead of the +260 a parlay would offer.

On the surface this looks like a bad trade — giving up massive payout for a modest spread adjustment. And often that intuition is correct. But the math depends entirely on how much cover probability those extra points actually buy you.

The Core Question: How Much Probability Do You Gain?

Not all teaser points are created equal. Moving a spread from -13.5 to -7.5 covers a range of margins that are relatively uncommon. Moving from -7.5 to -1.5 covers margins that occur far more frequently, because NFL scoring clusters around certain numbers.

The EV of a teaser comes down to a simple comparison:

• Combined cover probability of all legs at their teased spreads
• Break-even probability implied by the book's teaser payout odds

If your combined probability exceeds break-even, the teaser is +EV.

Calculating Cover Probability

Step 1: Back Out the True Line

Each teaser leg starts as a normal spread bet. From the book's spread and odds, we extract the implied true line using the inverse normal CDF:

$$\mu = s - \sigma \cdot \Phi^{-1}(p_{\text{cover}})$$

where $s$ is the posted spread, $p_{\text{cover}}$ is the implied cover probability from the odds, and $\sigma$ is the sport-specific standard deviation (about 14.2 for NFL, 22.6 for NCAAF).

Step 2: Cover Probability at the Teased Spread

With the true line $\mu$ in hand, the probability of covering the teased spread $s_t = s + \text{teaser points}$ is:

$$P(\text{cover}) = \Phi\left(\frac{s_t - \mu}{\sigma}\right)$$

For a -7.5 spread at -110 teased by 6 to -1.5:

$$\mu \approx -7.5 - 14.2 \cdot \Phi^{-1}(0.524) \approx -8.35$$ $$P(\text{cover at } {-1.5}) = \Phi\left(\frac{-1.5 - (-8.35)}{14.2}\right) \approx 68.6\%$$

Step 3: Combined Probability and EV

For independent legs, the combined probability is the product:

$$P_{\text{combined}} = \prod_{i=1}^{n} P_i(\text{cover})$$

The break-even probability for a teaser paying at American odds $d$:

$$P_{\text{BE}} = \frac{|d|}{|d| + 100} \quad \text{(for negative odds)}$$

Expected value as a percentage of breakeven:

$$\text{EV\%} = \frac{P_{\text{combined}} - P_{\text{BE}}}{P_{\text{BE}}} \times 100$$

Key Numbers: Why Some Legs Are Better Than Others

NFL games don't land on every margin equally. Due to the scoring structure (field goals = 3, touchdowns + PAT = 7), final margins of 3 and 7 occur far more frequently than neighboring numbers. The margin lands on exactly 3 about 15% of the time, and exactly 7 about 9% of the time.

This means a teaser leg that moves through 3 or 7 gains more cover probability per point than one that doesn't. Secondary key numbers 10 (field goal + touchdown) and 14 (two touchdowns) matter too, though less dramatically.

The calculator shows which key numbers each leg crosses, so you can see at a glance whether your teaser points are landing in high-value territory or being spent on margins where games rarely land.

Examples

Spread	Teased (+6)	Key #s Crossed	Value
-7.5	-1.5	3, 7	High — crosses both primary key numbers
-5.5	+0.5	3	Good — crosses 3 and gets past zero
-3.5	+2.5	3 (barely)	Moderate — crosses 3 but not 7
+2.5	+8.5	3, 7	High — crosses both going the other direction
-13.5	-7.5	10	Low — only crosses 10, misses the big two

Common Teaser Payouts

Format	Typical Payout	Break-even
2-team, 6 pts	-120 to -110	54.5% to 52.4%
2-team, 6.5 pts	-130 to -120	56.5% to 54.5%
2-team, 7 pts	-140 to -130	58.3% to 56.5%
3-team, 6 pts	+150 to +180	40.0% to 35.7%

Shopping for the best teaser payout across books is critical. The difference between -110 and -130 on a 2-team teaser shifts break-even by 4 percentage points — often the difference between +EV and -EV.

NFL vs. NCAAF

College football has the same key numbers but a much larger scoring standard deviation (~22.6 vs ~14.2). The wider distribution means each teaser point buys less relative probability. The same 6-point teaser that might be +EV in the NFL is typically -EV in NCAAF because the probability gain is smaller relative to the payout discount.

Limitations

• Independence assumption: The calculator assumes legs are independent. Correlated legs (e.g., same-game legs or games with shared factors) violate this — use the SGP Analyzer for correlated bets.
• Normal distribution: Real scoring margins have slightly heavier tails and point masses at key numbers. The CDF model is a close approximation but not exact.
• Line accuracy: The true line estimate depends on the input odds. Stale or soft lines produce unreliable results. Pinnacle closing lines give the best input.

Using the Calculator

Enter each leg's spread and odds as quoted by the book, select your teaser size, and enter the book's teaser payout odds. The calculator shows per-leg cover probabilities, which key numbers are crossed, and whether the combined probability exceeds break-even. Positive EV means the teaser is worth taking at that payout; negative means the book's discount more than offsets the extra points.