Howdy Hivers
All outside activities have been rained off today, so my attention has been on productive things I can do indoors. One of my favourite activities is taking money off the bookmakers, and I thought this may be of interest to other people who might want a small stream of fairly regular income. I was discussing this with 
The first thing to note here is that I am based in the UK where gambling is something of a national pastime, and all references are to UK bookmakers. I know that not every country has access to the range of services we get here.
No Risk Betting
Put simply, I am going to place a bet with one bookmaker, and then bet on the opposite occurring with another. More specifically I will lay the bet at a betting exchange, more of which later.
It is entirely possible to do this and make a guaranteed profit. The easiest way to do this is by keeping an eye out for special offers where you receive boosted odds from a bookmaker.
So, here we go. Stay with me, the maths look a little complex at first, but I will step through them.
Today's offer, boosted (very good) odds on the 4:10 at York:
Decimal Odds
If you are new to this, the first thing you need to do is convert the traditional fractional odds to decimal, because the decimal odds are so much easier to use.
7/4 = 2.75
So, if you bet £10 on Samburu to win you will win 7/4 * 10 = £17.50 plus your £10 stake back = £27.50
The Magic
Ok, so I am going to the betting exchange next, which differs from the traditional bookmakers in a few ways. However for the purposes of today's fun all we need to know is we can lay Samburu to win today. Essentially we are betting on it to lose at the exchange because we have the win covered at William Hill, in this example.
Here's what the exchange has for us:
So, we are getting 2.28 to lay Samburu which is considerably lower than the 2.75 we got at the bookie on Samburu to win.
This means profit!
Laying a Bet
This can seem a little daunting at first, as it differs from betting on a win. Here we place a stake in the hope that the horse doesn't win the race, and this gives us a liability if it manages to win. The amount of liability depends upon the odds.
If our horse Samburu doesn't win the 4:10 we will receive our stake from the Exchange minus a small commission. (2% in this case).
If our horse Samburu manages to pull off the win, our liability will be deducted from my balance at the exchange.
The Final Calculation
In a nutshell I am going to calculate how much to stake at the exchange, so that whether Samburu wins or loses I will make the an equal amount of profit.
The maximum I can bet on Samburu at the boosted odds of 2.75 is £10.00, this is a condition of the special offer. This will potentially give us a win at the bookies of £27.50.
The magic formula to calculate the exchange stake is this:
bookie win / (exchange odds - commission rate)
So 27.50 / (2.28 - 0.02) = £12.17
Simpler than it looks right?
The betting exchange liability on a £12.17 stake @ odds of 2.28 is £15.58. The exchange will calculate this for you, but it's simple enough maths:
liability = stake * (odds - 1) = 12.17 * 1.28 = 15.58
Guaranteed Profit
The final stage is to demonstrate the two outcomes:
If Samburu wins the race-
We win £27.50 from the bookie, where we staked £10.00.
We lose our liability of £15.58 at the exchange.
Total profit = bookie win minus bookie stake minus liability
= 27.50 - 10.00 - 15.58 = +£1.92
If Samburu fails to win-
We lost our £10 stake at the bookie.
We won our £12.17 stake at the exchange less 2% commission
Total profit = exhange win minus commission minus bookie stake
= 12.17 - 0.24 - 10.00 = +£1.93
So, either way No Risk Betting gives us a 19% return on our investment. Not bad for a 5 minute maths workout!
OK, so nobody is going to become a millionaire using this little trick but it's a nice source of extra beer money and there are many types of special offers that can be used. I will demonstrate these in future posts.