Bankroll Management for Beginners (Units, Flat Bets, and Real Math)

Most beginning bettors lose money for one of two reasons: they bet at -110 and win below 52.4%, or they manage their money so badly that one bad week wipes out a month of good ones. The first problem is hard to solve quickly. The second one is easy to solve, today.

This chapter is about the second one.

Your bankroll is what you can lose

Step one: pick a number. Your bankroll is the amount of money you're willing to lose without it changing your life. Not your savings. Not your rent money. Not money you need next month. Money you can lose.

Most casual bettors should be in the $500–$2,000 range. Bigger bankrolls let you bet more comfortably; smaller ones force more discipline. Both work. What matters is that the number is honest - that you'd be annoyed but not destroyed if you lost it all.

Units, not dollars

Once you have a bankroll, every bet should be sized as a percentage of it - a "unit." Most disciplined bettors use 1% per bet, sometimes 2% on plays they especially like. So:

The reason for sizing in units instead of dollars is simple: it survives changes in your bankroll. If you double your money, your unit doubles too - automatically. If you lose half, your unit shrinks - automatically. The percentage stays constant; the dollar amount adjusts.

Flat betting is the right starting point

Flat betting means risking the same number of units on every bet, regardless of how confident you are. 1 unit on every play, every time.

It's boring. It's also the right place to start, for three reasons:

• It removes emotion. Tilt-fueled bets - chasing losses, doubling up on the late game, firing five units on a "lock" - are how bankrolls die.
• It makes your results easy to read. If every bet is the same size, your win rate and your dollar P&L tell the same story.
• It buys you time. Even great bettors lose 40% of their bets. Flat sizing makes the variance survivable.

What a $1,000 bankroll actually looks like over a season

Say you have a $1,000 bankroll, you bet 1 unit ($10) per play at -110 odds, and you place 3 bets a day for the 6-month MLB season. That's roughly 540 bets.

Three rough scenarios:

• Average bettor (50% win rate): 270 wins, 270 losses. Net: -540 × $10 × 0.045 vig = -$243. You lose roughly a quarter of your bankroll over a season just to vig.
• Solid bettor (54% win rate): 292 wins, 248 losses. Net: +$200. A 4-point edge over break-even produces roughly a 20% return on your bankroll.
• Sharp bettor (57% win rate): 308 wins, 232 losses. Net: +$758. A 7-point edge nearly doubles the bankroll. This is the high end of what real-world bettors achieve.

The takeaway: small edges produce real money over real volume, but only with discipline. A 54% bettor who flat-bets 1% units survives bad runs. The same 54% bettor who five-units losses to "make it back" can blow up the bankroll inside a month.

The Kelly Criterion (briefly, with a warning)

Kelly is a formula that tells you the mathematically optimal bet size given your edge. For a +EV bet, Kelly recommends a fraction of your bankroll equal to (edge / odds). For a small edge at -110 odds, that comes out to a small percentage - often 1% to 3%.

The catch: Kelly requires you to know your true win probability. Beginners don't. Estimating "I think this is a 56% bet" is not the same as it actually being a 56% bet, and Kelly punishes overconfidence aggressively. Most bettors who use Kelly use a "half Kelly" or "quarter Kelly" specifically to compensate for the fact that they're overestimating their own edge.

For Phase 1 of your betting life - the first year - flat 1% units do almost the same job as half Kelly with much less mental overhead and much less downside if you're wrong about your edge. Start with flat. Move to fractional Kelly only once you have 500+ bets of tracking and a real measured edge (we'll cover that in Chapter 9, CLV).

The deposit-and-track rule

One last piece of mechanics. Whenever you deposit money to a sportsbook, write it down. Whenever you withdraw, write it down. Your true bankroll is "current account balance + all withdrawals - all deposits." It is shockingly easy to lose track of how much you've actually put in over a season, and the only thing that matters at the end of the year is "did the money I put in come back, and then some."

We'll come back to tracking - for both bankroll and skill - in Chapter 9 (Closing Line Value) and Chapter 28 (Tracking Every Bet). For now, the rule is: write down every deposit, every withdrawal, every bet.