This unique article separates Premium Bond fact and myth, using the UK's only Premium Bond Probability Calculator. Nearly half the UK has money in these Bonds, they generate the government cash and with over £36 billion held in them, are by far the biggest single savings product around. The aim here is to answer the most important question… “are they worth it?”
The specially-developed Premium Bond Calculator reveals what your realistic chance of winning different amounts are depending on how many bonds you have and how long you hold them. Then it enables you to compare this to a top savings account and inflation.
More chance of an icecube in hell? |
All Premium Bond rate changes are in the free MoneySaving weekly e-mail
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The Basics - How do Premium Bonds work?
Premium Bonds are simply a savings account you can put money in (and take it out when you want), where the interest paid is decided by a monthly prize draw, where you can win between £50 and £1 million tax-free.
The minimum holding is £100 (or £50 for monthly standing orders) and the maximum is £30,000. So put a grand in and you get 1,000 £1 Bonds, each is then individually entered into the prize draw. They can be bought online at NS&I’s website, in Post Offices, over the phone or through a regular monthly payment by standing order.
The bonds enter the prize draw one calendar month after purchase and continue until you cash them in, which can be any time, though it takes up to eight days to withdraw.
Some quick Premium Bond facts:
- The capital is very safe. You don’t risk the money you put in, only what interest you’ll get, and Premium Bonds are operated by NS&I which, rather than being a bank, is backed by the Treasury.
This is a boon only available with NS&I or Northern Rock products, 100% safety for your cash. During the current Credit Crunch it may be worth considering this safety (read Are Your Savings Safe? article). - Who can buy them? Anyone aged over 16 can buy Premium Bonds and they may be held in the name of under 16s by parents or guardians and grandparents (but not anyone else).
- Winnings can be re-saved. Rather than receiving the winnings, you can opt to have them automatically buy more Bonds. The idea is this works in a similar way to Compound Interest in a normal savings account, as then your winnings have a chance at winning.
- The winners are decided by random draw. NS&I sexes-up the draw by the personification of the IT equipment, in other words, it calls it ERNIE (electronic random number indicator equipment); in reality it's a simple, audited, random number process where every Bond has an equal chance of winning no matter where or when it was bought.
- In a typical draw, each bond's chance of winning a million is 18 billion to 1. Of 36 billion pounds in Premium Bonds, each month, there's around 1.7 million prizes given out of between £50 and £1 million each. Over 1.4 million of these are £50s, 190,000 are £100 and the remaining 8,000 or so are between £500 and a million (only two are £1 million though).
- Claiming old prizes/bonds. There are currently £30 million worth of prizes unclaimed. To check if any are yours go to the NS&I website; there's no time limit to claims (also read the Reclaiming Lost Assets article).
Premium Bonds can't be passed on, so either use them or cash them in. If a Premium Bond holder dies, the bonds only remain eligible to win for 12 months – after that they just sit there. Thus if you believe a late relative had bonds, check it out as soon as possible.
There's heavy positive spin put out about Premium Bonds, after all NS&I is government backed, and they help generate government funds and cash flow. Yet the payout is much worse than many believe.
You’re likely to win even less than the interest rate.
The value of prizes paid out is determined by an interest rate, which is currently 3.4%, though it's changed, usually following a change in Bank of England UK rates. This means if you owned every Premium Bond in existence, the amount won over a year would be equal to 3.4% of what you put in. So very roughly, on average for every £100 put into Premium Bonds, you'd expect a £3.40 annual return.
Yet because of the way the prizes are allocated, the majority of people will win much less than the interest rate anyway. There’s a full explanation of why this happens later, but for now you can use the Premium Bond Probability Calculator to see how likely you are to win an amount equal to the interest rate.
They’re worse than the top savings accounts.
Yet even if we assume you would win the £3.40 a year for every £100 saved, and compare this to the Top Savings Accounts or Cash ISAs, it’s usually disappointing.
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How Premium Bonds Compare (May 2008) | ||||
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Returns based on the interest rate | ||||
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Interest Rate |
Non Taxpayer |
Basic Tax |
Higher Tax | |
| Premium Bonds (1) |
3.4% |
£34 |
£34 |
£34 |
| Top Savings Account |
6.5% |
£65 |
£52 |
£39 |
| Top Cash ISA |
6.5% |
£65 |
£65 |
£65 |
|
(1) Someone with average luck is actually likely to win less than this | ||||
Clearly, even if you did get the interest rate, compared to a tax-free cash ISA you're always on a loser. The only time Premium Bonds interest rate wins is for higher rate taxpayers who've used up their cash ISA allowance, and even then it‘s marginal.
Don’t think of it as ‘winning’
The great sell is ‘the lottery effect,' the chance of winning a dream, and there is of course the chance of winning a million. Equally you could be the next space-walking astronaut, and you’re odds probably aren’t that dissimilar! Your chance of winning the jackpot per £1 spent on the lottery is one in 14 million, far out-stripping the one in 18 billion chance of becoming a millionaire through the Premium Bond draw.
The fact the payouts are commonly referred to as a ‘win’ rather than an ‘interest payment’ is psychologically devious. Comments like, “my friend wins £50 every few months” mislead; on clinical evaluation, someone with £10,000 of Bonds should ‘win’ £340 a year; that’s roughly £50 every other month; yet the same cash in a savings account would ‘win’ over £50 every month or £650 a year.
Worse still, compare the Premium Bond interest to retail price index inflation (RPI), the nearest estimate to the rate at which prices rise. It’s currently 3.8%, significantly higher than the Premium Bond interest rate, so any cash you have in bonds is increasing more slowly than the prices of everyday goods. This means by holding bonds the real amount of money you have is decreasing.
You can compare how much you are likely to make with Premium Bonds to inflation and the top savings accounts easily using the Premium Bonds Calculator.
Are they ever worth it?
Look at Premium Bonds with a clinical financial eye and as I've already explained, they're only worth considering if you're a higher rate taxpayer, and have used up your cash ISA allocation. Yet some will win more than the average, not many, but a few.
Put £100 in Premium Bonds, calculate the probability and 95% of people won't win a penny over a year, but one in 20 will win £50 or more! And if you're that lucky person, this is a great return. Yet the odds of winning big get very long; use the calculator to gauge your chances.
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Premium Bonds aren’t as good as they first appear
It's all about the actual prize distribution. Below is the distribution of prizes in a typical monthly draw. This can and does change (for example sometimes there are extra £1 million prizes in promotional draws), but it's still relatively few and doesn't change the chance for most.|
A Typical Draw (May 2008) | ||
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Prize Level |
Amount per month |
Odds of winning per £1 bond |
|
£1 million |
2 |
1 in 18,150,000,000 |
|
£100,000 |
8 |
1 in 4,542,000,000 |
|
£50,000 |
17 |
1 in 2,137,000,000 |
|
£25,000 |
34 |
1 in 1,068,000,000 |
|
£10,000 |
84 |
1 in 433,000,000 |
|
£5,000 |
167 |
1 in 217,600,000 |
|
£1,000 |
2,059 |
1 in 17,647,000 |
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£500 |
6,177 |
1 in 5,882,000 |
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£100 |
189,503 |
1 in 191,700 |
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£50 |
1,453,588 |
1 in 24,997 |
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£0 |
36,334,422,701 |
1 in 1.00004 |
Why most people win less than the interest rate
Even though Premium Bond rates stack up poorly compared to decent savings rates, even that’s still misleadingly generous; the real expected payout is much less, as it's massively skewed by the distribution of the prizes.
This is tricky to understand, so let me start with a simple example. Suppose there a contest offered a £1,000,000 prize and allowed a million people to buy a ticket costing £1. It could then be argued the average winnings per ticket were £1, even though 999,999 people would win nothing.
A similar, though less drastic, effect is happening with the Premium Bond interest rate; it says the payout is 3.4%, so you'd expect to win £3.40 per £100. Yet of course this is impossible, there isn't a £3.40 prize; you can either win nothing, £50, or more than £50. The big jackpot prizes, won by a miniscule number of people, skew the payout average and make the interest rate look much more generous than it is.
The Premium Bonds calculator takes all this into account, and through statistical analysis, reveals what you're really likely to win. The stats it throws up aren’t pleasant reading for Premium Bond holders.
- £100 over a year. Put the minimum £100 in and the interest rate predicts a win of £3.40 over a year - yet that’s impossible as the smallest prize is £50. In fact 19 out of every 20 people with this amount won’t win a thing; leaving only one in 20 winning £50 or more.
- £1,000 over a year. Put £1,000 in Premium Bonds over a year and while the interest rate predicts a £34 win, the majority of people (58%) still win nothing.
- £30,000 for a year. Even if you put the biggest amount you're allowed to in Premium Bonds, your chance of winning the million in a year is still over 1 in 50,000.
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Let’s get really nerdy: bizarre probability outcomes!
On the surface Premium Bonds don’t look to be complex. NS&I happily lists on its website enough data to allow anyone with a calculator to work out the chance of one bond winning a £50 prize over a month (1 in 22,000 by the way).
Yet to work out the chance of someone with five thousand bonds winning £500 or more includes countless variables. To win £500 in one go could be one £500 prize, or five £100 prizes, or ten £50 prizes; or a combination of them; yet to win more than £500 holds scores of variables.
Plus of course, the draws are monthly, so if you’re calculating the assumed winnings over 5 years; it actually means you’re calculating the interaction of probabilities for over 60 draws to get the various answers. This is why, until now, the probability was virtually impenetrable. In the end we cracked it using a very advanced multinomial probability equation devised by a post-doctoral cosmology statistician!
And if you look at the outcome of this in practice, when you look at the table below you’ll see some rather bizarre results.
| How do premium bonds stack up? | |||||||
| Amount of Bonds | Odds of winning £0 | Chance of beating inflation (RPI) | Chance of beating a Savings Account | ||||
| Amount needed to beat inflation | Odds of earning this or more with Premium Bonds | Basic rate | Higher Rate | ||||
| Interest in Savings Account (1) | Odds of earning this or more with Premium Bonds | Interest in Savings Account (1) | Odds of earning this or more with Premium Bonds | ||||
| Over 1 year | |||||||
| £100 | 95% chance | £3.80 | 1 in 20 | £5.20 | 1 in 20 | £3.90 | 1 in 20 |
| £1,000 | 58% chance | £38 | 1 in 2.5 | £52 | 1 in 7 | £39 | 1 in 2.5 |
| £5,000 | 6% chance | £190 | 1 in 2.5 | £260 | 1 in 8.5 | £195 | 1 in 2.5 |
| £30,000 | 1 in 12 million | £1,140 | 1 in 4 | £1,560 | 1 in 25 | £1,170 | 1 in 5 |
| Over 5 years | |||||||
| £100 | 76% chance | £19 | 1 in 4 | £26 | 1 in 4 | £19.50 | 1 in 4 |
| £1,000 | 6% chance | £190 | 1 in 2.5 | £260 | 1 in 8.5 | £195 | 1 in 2.5 |
| £5,000 | 1 in 800,000 | £950 | 1 in 4 | £1,300 | 1 in 18.5 | £975 | 1 in 5 |
| £30,000 | Negligible | £5,700 | 1 in 8.5 | £7,800 | 1 in 62.5 | £5,850 | 1 in 11.5 |
| (1) Top Saving Account paying 6.5% interest, it assumes the interest is withdrawn, not compounded as this is how most people use Premium Bonds. Note where the odds are better than 1 in 2, they are expressed as a percentage | |||||||
For example you’ve more chance of beating a savings account interest rate with £1,000 than with £5,000. All but stats nerds should skip the explanation I'm about to give, as it really is quite esoteric. This is because the likelihood of winning peaks at or just under a payout value which can be made up from a combination of prizes, so where the amount needed to beat the savings account is only just above one of those, the odds of beating it increase.
The easiest example I can come up with is… put £960 in a savings account and a basic rate taxpayer earns £49.90; therefore a Premium Bond holder only needs one £50 prize to beat it, and the chance of winning less than this is 58%. Yet someone with £1,000 in a savings account earns £52, to beat this takes at least 2 x £50 wins or 1 x £100 win, even though there’s only 40 quid more, thus the odds of winning less jumps to 85%.
A Summary: The Results
Look at Premium Bonds with a clinical financial eye and they’re only worth considering as a serious place to put savings, if you’re a higher rate taxpayer, who has used up your Cash ISA allocation.Yet for those who like a flutter, as Premium Bonds do protect your cash, it's fine to put a non-significant portion of your money in them, more for fun than returns. However before deciding, use the calculator to look at the real odds; and if you’re willing to take the gamble after that – then it’s fine.
Many people often think “I’m likely to get about 3.4% and there’s a small chance of winning a million”, the main point is this isn’t correct. You’re actually likely to get quite a lot less than 3.4% and there’s a negligible chance of winning a million. Take a look at the chances, but beware, it ain’t pretty reading.
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