Cash as an asset class

Cash is an integral part of building any investment portfolio. It is the only asset class that doesn't pose any capital risk – meaning that you won't lose any actual money by placing your money in 'cash.'

Cash helps to protect your money. If you're uncomfortable with losing too much money, you can keep much of your portfolio in cash and then diversify into other, riskier asset classes. Remember the risk/reward trade off though - the more you have in cash, the lower returns you might receive.

However, that's not to say that there aren't any risks with cash – you could see the spending power of your money fall if inflation is higher than the interest rate you receive. This is known as inflation risk.

Action point: Which? investment portfolios - we have created a unique set of investment portfolios that can help you decide where to invest your money, balanced with how much you're willing to put at risk. 

Cash Isas

In the 2012/13 tax year, you can place up to £5,640 into a cash Isa and you can top up your Isa account annually. Any gains you make from the interest you’re paid are free of tax. Most savers can benefit by using their annual Isa allowance before putting any remaining funds into ordinary taxed accounts.

But remember that if you want to move your Isa to a higher interest product, apply to transfer it rather than taking out the money and reinvesting it yourself. This is because if you withdraw your money and then reinvest it during the same tax year, you'll be using up all or part of your tax free allowance for that tax year.

Action point: Best Rate cash Isas - check out the latest rates on tax-free savings accounts

Savings accounts

Once you have used up your cash Isa allowance, you can also place your money in a taxable savings account. In choosing one, you need to look carefully at its features as well as the interest rate it pays. 

Instant or easy-access accounts suit those who may need to withdraw money at short notice. They are suitable accounts for rainy day funds but don't offer much growth above inflation, if any at all.

Higher rates of interest are often offered to savers when they open a new account. These bonus rates commonly last for 6-12 months, reverting to a lower rate thereafter, so it is worth making regular checks to confirm the rate you will receive.

Action point: Best Rate savings accounts - check out the latest rates on savings accounts

National Savings & Investments (NS&I)

NS&I is a government backed savings and investments service, offering a range of products to help you save money. As it’s run by the state, it means that 100% of your savings are fully protected, better than the £85,000 that the UK’s Financial Services Compensation Scheme provides should a bank go bust.

NS&I offers a range of products from premium bonds, to simple cash accounts, children’s savings products and the popular inflation-linked savings certificates. NS&I don’t generally provide market-beating interest rates on their products but if it’s complete safety you’re looking for with your cash, they could be a good option

Action point: Are my savings safe? - see how your savings are protected

Money market funds

Money market funds are collective investment schemes, usually in the form of unit trusts and open ended investment companies (Oeics), which invest your money in cash or equivalents to cash, like short term loans to the government (known as Treasury Bills) that pay a fixed rate of interest (like a gilt).

There are a couple of advantages to investing in a money market fund. Firstly, managers of these funds investment in many different types of cash–like products, and therefore you can diversify your portfolio away from having all of your money tied up in just one savings account or cash Isa.

Also, if you are building a portfolio of investments, investing in a 'cash' fund can allow you to easily keep a check on its performance along with your other fund investments.

However, with money market funds you could lose some of the capital value of your money, unlike a deposit account or cash Isa. You're also charged an annual management fee, usually around 1%, which in a low interest environment, can reduce the any returns the fund makes.

Action point: Different types of investment - find out more about unit trusts, Oeics and fund charges.

More on this...

• The Which? investment portfolios - use our unique tool to pick the right investment
• A guide to unit trusts and Oeics - get to grips with these investment products
• Call the Which? Money Helpline - if you  have a query about investing your money