Got a Marcus or Saga easy-access account? 100,000s can boost their savings by 0.1 percentage points, but you'll need to act

Marcus offers two easy-access savings products:

• A standard savings account*, where any interest earned counts towards your personal savings allowance (though the majority of UK savers won't be affected by this). See our Top savings guide for the best buys.

• A cash ISA*, which is a tax-free savings account where deposits are restricted to £20,000/year. See our Top cash ISAs guide for the best buys.

Saga, meanwhile, offers just one account:

• A standard savings account*, where – as with Marcus' offering – any interest earned counts towards your personal savings allowance. See our Top savings guide for the best buys.

All three accounts let you make unlimited withdrawals without being penalised – though replacing withdrawn money into Marcus' cash ISA will eat into your £20,000 annual ISA allowance. These accounts previously paid 0.4%, but this has risen to 0.5% this month for new customers, though existing customers may also be able to get the higher rate too (see below).

Already a Marcus or Saga saver? How to boost your rate to 0.5%

Crucially, with Marcus and Saga savings you're paid an underlying rate of interest (currently 0.4% for existing savers), but you can also sometimes get a bonus rate on top for 12 months. Right now, anyone with Marcus or Saga savings can get the bonus rate, which adds 0.1 percentage points to the interest you earn, taking it to 0.5% in total.

If you've already got a bonus, which you may do depending on when you signed up, you'll already be earning at least 0.5% (some customers may have an existing bonus rate that's higher than the one currently available) and will continue to get the bonus until 12 months after you first got it. If you don't already get the bonus though, you can now get it with a few clicks – here's how:

1. Log in to your Marcus or Saga account in the normal way.

2. Click 'View' next to the account name. This will show you if you've already got an active fixed bonus, and when this will expire.

3. If you don't have the bonus already, select 'Review your savings'. You'll find this under 'Bonus rates' (at the bottom left of the desktop).

4. Click 'Renew your bonus'. You'll then receive confirmation that the bonus has been added and your rate will be upped to 0.5%.

New Marcus or Saga saver? You'll automatically get the bonus rate 

If you open a new Marcus savings account or have done since 1 July, you'll automatically get the 0.1 percentage-point boost. If you open a new Saga account or have done since 9 July, you'll also automatically get the same boon.

This means you'll earn 0.5% for now, and even if Marcus or Saga lower the rate of these accounts, which is variable, you're guaranteed interest of at least 0.1% for a year. Keep an eye on the rate though, as if it does drop you may be able to beat it, and diarise to check again in 12 months when the bonus comes to an end.

Marcus and Saga's savings accounts and ISA are best buys

If you want a normal savings account with instant and unlimited access to your cash, Marcus and Saga are currently our joint top picks with their 0.5% rate, including the 0.1% bonus. While other providers also pay this interest rate, none have the benefit of big-name backing like Marcus and Saga do. Both accounts can be opened online with £1.

When it comes to easy-access cash ISAs, Marcus tops the table once again – you can open this account online and deposit between £1 and £20,000 (less if you've already paid into a cash ISA this tax year). Saga doesn't currently offer cash ISAs. See our Top cash ISAs guide for the best buys.

But while standard easy-access savings rates have gradually begun to recover following a recent slump, they still pay very little compared to other types of savings accounts. There are a couple of special accounts for small amounts of money that can pay up to 2%, for example – you can find out more in easy-access savings.

You can also get a better rate if you consider fixing, with up to 1.66% available over five years – see top fixed-rate accounts for further details.