This week's top ISAs explained

The best easy access cash ISA rates

While Sidekick continues to top our easy access ISA chart this week, its Cash ISA pays a lower 4.61% AER monthly after the provider cut rates. Its important to note that this headline rate includes a six-month bonus of 1.38%, which applies to new deposits on balances between 1 and 20,000; after six months and on balances above 20,000, the rate reverts to a lower 3.23% AER. This ISA is only available via mobile app and allows savers to add to and withdraw from their savings pot without restriction. Moreover, as it follows flexible ISA rules, savers can replace any withdrawn funds to their account within the same tax-year without affecting their ISA allowance. Savers who transfer at least 10,000 to Sidekicks Cash ISA could receive a cash bonus of up to 500 (paid after 12 months), although Sidekick wont pay this bonus if savers close or transfer out their cash ISA in full during the 12-month bonus period. See more details on how Sidekicks ISA transfer cash bonus offer works on our chart.

Meanwhile, Progressive BS pays a slightly lower 4.60% AER yearly on its 1 Year Double Access Cash ISA Account (Issue 19), which can be opened and managed in branch or by post, and its Online 1 Year Double Access Cash ISA (Issue 4), which is available online. These ISAs both require a minimum opening deposit of just 1 and dont set any limits on further contributions. However, although these ISAs follow flexible ISA rules, savers should bear in mind that they only allow up to two withdrawals per tax-year (withdrawals from the online ISA must be made via a nominated account). The ISAs will revert to an instant access cash ISA on maturity, or if savers make three or more withdrawals during the one-year period.

Sitting in third position on our easy access ISA chart is Trading 212s Cash ISA Promo Rate, paying 4.56% AER (including a 0.96% bonus for 12 months). Savers can access this bonus by applying via Moneyfactscompare.co.uk by 6 September (they may need to enter the promo code MFC during the opening process). This ISA can be opened and managed online or via mobile app and asks for a minimum opening deposit of 1. It allows further deposits and withdrawals without restriction and comes with the extra perk of being a flexible ISA. Before applying for this ISA, check the provider's partner banks to make sure your money will be fully covered by the Financial Services Compensation Scheme (FSCS).

The best fixed cash ISA rates

The leading one-year fixed ISA dropped this week after Isbank lowered rates. AlRayan Bank now tops our one-year ISA chart with its 1 Year Fixed Rate Cash ISA via Meteor Savings paying an expected profit rate of 4.72% AER on maturity on a minimum opening deposit of 1,000. Available via the online Meteor Savings platform, this ISA doesnt allow any further contributions after the opening deposit and only permits earlier access to funds on account closure, subject to receiving a lower expected profit rate of 0.05% for 90 days (or the number of days the ISA has been open if less than 90 days).

Savers wanting to secure a guaranteed return for longer will find the highest two-year and three-year fixed ISA rates rose to 4.77% AER and 4.80% AER, respectively, after Vida Savings hiked rates on its 2 and 3 Year Fixed Rate ISAs. Its 5 Year Fixed Rate ISA also increased this week to 4.85% AER to lead our five-year ISA chart. Savers can open these ISAs (which pay interest monthly or on anniversary) online by depositing 1,000 or more and can subsequently manage them online or via mobile app. They can continue to add to their account for the next 21 days but, if they want to withdraw from their ISA before the end of the term, they will incur a 180-day (two-year), 270-day (three-year) or 360-day (five-year) loss of interest penalty.

The best notice cash ISA rates

Theres no change to the leading notice ISAs this week, with Dudley BS continuing to pay the top rate on up to 30-day notice ISAs of 3.70% AER. Its 30 Day Notice Cash ISA Issue 4 and 30 Day Notice Cash ISA Online Issue 3 pay this rate yearly on an opening deposit of 100 or more, with the former account available in branch or by post while the latter option is only available online. Savers can add to these ISAs without restriction but will need to wait 30 days before accessing any withdrawals, unless theyre willing to incur a 30-day loss of interest penalty to receive their money sooner.

The Stafford BS pays the leading rate on ISAs with a notice period of up to 60 days and up to 90 days. Its Notice 60 Cash ISA pays 4.00% AER yearly while its Notice 90 Cash ISA offers a higher 4.10% AER, also paid yearly. Both ISAs can be opened online, in branch or by post with a minimum deposit of 100, which savers can add to without restriction. However, they can only make up to four withdrawals per society year (which runs from 1 November to 31 October). The Stafford BS doesnt permit earlier access to funds in these accounts, so savers will need to wait 60 days or 90 days before receiving any money they withdraw.