Find out about the pros and cons of using National Savings & Investments products.
When you think of NS&I - or National Savings & Investments - the first thing that probably comes to mind is Premium Bonds, which is NS&I's most popular product.
But the HM Treasury-backed body also offers a number of other savings options.
NS&I savings and investments are backed by HM Treasury, which means any money you invest is 100% safe.
This might make NS&I an attractive option for savers with a nest egg larger than the amount backed up by the Financial Services Compensation Scheme (FSCS).
It offers products online, over the phone and by post and over 25 million customers in the UK save and invest with it.
Although NS&I offers the ultimate savings security, that doesn't necessarily mean its products will give you the highest returns on your investment.
It's important to compare savings accounts, Individual Savings Accounts (Isas) and bonds to find the right product for your situation.
NS&I offers various tax-free and taxed saving vehicles, some of which may only be suitable for certain age groups.
NS&I offers a number of taxable savings options, which means you'll be liable to pay income tax on returns.
For some accounts, although the interest is taxable it's paid without the tax taken off. This means you'll need to declare the interest to HMRC each year on a tax return and pay any tax due.
A Direct Saver can be managed online and operates in a similar manner to other easy-access savings accounts.
Guaranteed Growth Bonds aren't always on general sale - they're sold in 'issues', each with a specific interest rate that's guaranteed for the period of the investment term
An NS&I Investment Account is another instant-access option for those who prefer to handle their savings by post.
These are similar to other fixed-rate bonds and are open to anyone aged from 16 or over.
Guaranteed Growth Bonds aren't always on general sale - they're sold in 'issues', each with a specific interest rate that's guaranteed for the period of the investment term. Issues can be withdrawn by NS&I at any time.
They allow you to invest up to £1m per person, per issue, in a single lump sum.
These are similar to other Guaranteed Growth Bonds, but are only for people aged over 65.
A term is between a year and three years and the bonds are designed to be held for the full term - there's a penalty if the bond is cashed in before the end of the term.
You can buy more than one bond - so you could, for example, have both a one-year bond and a three-year bond.
The 65+ growth bonds were launched by Chancellor George Osborne in the March 2014 Budget when the minimum investment was £500 and the maximum £10,000.
Income Bonds accrue interest and pay it into your bank account each month.
This gives you a regular income from your savings but means that the bond account won't benefit from compound interest. You must be at least 16 to open an income bond.
You can keep depositing more money into your bond once opened and can cash the bonds at any time without penalty.
With most providers the only tax-free savings options are Isas. NS&I does offer these, but also has a number of unique, alternative tax-free products.
NS&I's Isa product works in the same way as any other, using your annual allowance to earn interest tax-free.
An Index-Linked Saving Certificate is a lump-sum investment that makes sure your money will keep up with inflation. It's held over a set period of time - an investment term.
As with guaranteed growth bonds, the certificates aren't always on general sale and are sold in issues.
Each year the investment's value moves in line with a measure of inflation called the Retail Price Index (RPI). The investment also earns a fixed interest rate daily on top of the index-linked rate, which is added to the certificate on each anniversary.
In times of below-inflation savings rates, index-linked certificates can offer market-leading rates.
Index-linked savings certificates are meant to be held for the full term and if you decide to access your investment prematurely you'll be subject to a penalty and will lose the index linking on your whole certificate for that investment year.
Premium Bonds are savings accounts which offer the chance to win tax-free cash prizes.
For each £1 invested you'll get a unique bond number, so the more you invest, the higher your chance of winning.
If you save £500, you'll get 500 bonds and 500 chances to win a cash prize. Cash prizes vary between £25 and £1m and there are two £1m prize draws every month.
Premium Bonds are one of the most popular saving options in the UK, with over 21 million people holding over £51bn in bonds in March 2015.
Once you've held your bonds for a complete calendar month, they're entered into a prize draw and have a chance to win. So if you invest your bonds in February, you'll have to wait until April for the chance to win.
These bonds don't earn interest - instead the interest funds the monthly prize draw.
Children's Bonds require a single lump-sum investment of between £25 and £3,000 in each issue.
They earn a tax-free fixed interest rate for five years, but there are interest penalties for cashing them in early.
The bonds are owned by the child but the parent, grandparent or guardian nominated on the application looks after the bond until the child's 16th birthday, at which point the child becomes responsible for the money.
Children's Bonds can be held in addition to Junior Isas.