From new tax rates on savings, to a pay-per-mile scheme for electric vehicles, via changes to pension contribution rules – this week’s budget included measures that will have an impact on household finances.

Here are some of the questions people wanted the Guardian to answer after Rachel Reeves sat down:

I am paying class 2 UK state pension contributions as I live abroad. Can I still obtain a UK state pension? I lived in the UK for 15 years before moving to Europe.

One measure that didn’t get much attention is the chancellor’s decision to make changes to how people can build up entitlement to the UK state pension if they have moved overseas. State pensions are based on national insurance contributions (Nics), and people can make extra payments, called voluntary Nics, to make sure they qualify for a good retirement income.

The budget included a change to the voluntary Nics people in your situation can make. From April 2026, you will no longer be able to use the cheaper class 2 Nics and will only be able to use class 3 ones. These cost five times as much, at £17.75 for every week’s worth of Nics you are making up.

Despite the increase, Steve Webb, a former pensions minister who is now a partner at the consultancy firm LCP, says: “Class 3 is still subsidised and represents exceptional value for money for those who can benefit.”

Another change was that people must now have lived in the UK for at least 10 years in a row, or paid 10 years’ of Nics here, before moving abroad. Those who haven’t will not be allowed to make any voluntary payments. This does not look like a problem for you.

The contributions you have already made will still count, and you will be able to make more at the cheaper rate before the change, so you will still benefit from a UK state pension when you reach the right age.

EVs are to be taxed at 3p a mile, but how will the mileage be determined?

The new tax, which will be on top of vehicle excise duty (VED), will be paid annually and based on how many miles you drive – and it will be paid upfront.

The plan is to launch the new charge in April 2028 and the proposals are still out for consultation, so things may change, but as things stand, drivers will estimate their mileage for the year ahead and pay either a lump sum or opt to spread their payment. At the end of the year, they will submit their actual mileage – this will be given at an MOT, or will be collected professionally if the car is under three years old. Any extra mileage will be paid for then, or any extra eVED will be refunded.

I drive an electric camper van and most of my miles are driven in Europe as I tend to use the bus here. Many camper owners will be in the same position as I am. Can the miles I drive abroad really be taxed in the UK?

I’m afraid the answer is yes – the government consultation document spells out that the decision to not set up a scheme which tracks where people drive means that mileage done outside the UK will also be counted for the purposes of the new charge. The change is designed to replace money lost from fuel duty, and, of course, petrol car drivers may pay this and then get on a ferry to France – but they will probably fill up before coming home, so EV drivers may feel that they are getting a raw deal. The Treasury has decided though that it is “proportionate to prioritise privacy and simplicity over a system of checks to deduct non-UK mileage”.

One thing to note is that the new EV tax will not apply to vans. The Treasury says the classification is up to the DVLA, so if it classes your camper as a van rather than a car you would be off the hook.

My wife uses a wheelchair and receives personal independence payment (Pip). We have a wheelchair-accessible EV that we purchased. Our previous cars were exempt from vehicle excise duty (tax class: “disabled”). Will we have to pay the EV excise duty and the mileage charge?

It’s bad news for you, too, I’m afraid. Because the new eVED is designed to tax drivers in a similar way to fuel duty, it is not being waived for those with disabilities: “eVED will apply to cars driven by those who are wholly or partially exempt from VED [vehicle excise duty], but where their petrol or diesel equivalents would be subject to fuel duty,” states the Treasury’s consultation on the new tax.

This means your wife will still benefit from her exemption to the existing annual VED – which is typically £195 a year on electric cars aged over a year – but you will face the 3p a mile charge.

I have about £50,000 in a cash Isa and add about £300 a month to my savings. I feel a bit nervous about investing. How will the change to cash Isas affect my current savings, and what would be the best way to save going forward?

Don’t worry! The cash Isa limit that is being talked about is an annual limit, so the money you already have in the tax-free wrapper is fine. After April 2026 you can also keep adding £300 a month as that comes to £3,600 over the year – well below the £12,000 cash Isa limit for under-65s (over-65s can still pay in up to £20,000 a year). An Isa may not always be your best bet, as they do not always offer market-leading interest rates. Depending on your other income, you may want to compare returns on other savings accounts.

That said, interest rates have come off their peak and are likely to go down as the Bank of England continues to try to tackle inflation, so – depending on what you are saving for – you might want to consider dipping your toe into the stock market, maybe by redirecting a small part of your monthly payment into a stocks and shares Isa. Regular payments are a good way to try stocks and shares as they smooth out falls; putting in a one-off lump sum is risky as if the market falls, it all goes down in value.

Can we be certain that the £150 claimed energy savings from April 2026 will be passed on to customers?

We can be sure that from April savings will be reflected in Ofgem’s energy price cap for Great Britain as the regulator has to take into account the costs providers face. These will no longer include the energy company obligation or 75% of the renewables obligation – or the VAT on these – so contribution to bills should be lower. According to the government, on the current price cap (£1,755) the changes would represent a saving of £134 a year.

However, that is not to say your bills will go down by that much. There are many other elements, including wholesale energy costs, that are factored into the cap, and your usage will ultimately determine how much you pay.

I am using the salary sacrifice pension contribution so my taxable gross salary stays below £100,000 and I can get access to free childcare. Will the changes mean my contributions become part of my taxable gross salary and make me miss out on the two childcare schemes?

The budget included the announcement that from April 2029 the national insurance relief on pension contributions made via salary sacrifice schemes will only apply to the first £2,000 paid in each year. It’s not clear how much you are paying in to your pension, but if it is more than that then you are right to want to know more.

Webb says there’s no suggestion that contributions above that level will be treated as taxable pay, so you could continue to put money into your pension and protect those other benefits – as long as your employer does not want to change what it offers. You will still get tax relief, but may see your take-home pay go down a little.

Employers will have to pay national insurance on contributions above £2,000 too now, so the schemes won’t be as attractive to offer – but they would have to pay NI if they were giving you the money in your pay packet, so they might be minded to continue with salary sacrifice.

You have a while before the changes are made. Ask your employer what it plans to do, and see if there are other salary sacrifice opportunities – some workplaces will let you lease an electric vehicle this way, for example.

I am using salary sacrifice but am above state pension age so I don’t pay national insurance – will that change when contributions are capped?

No – the Treasury has confirmed that national insurance will not be applied in this situation. It will only be charged on contributions over £2,000 if it would have had to be paid on the equivalent salary. You should be able to continue to make the payments as you do now.

My wife and I own a property that we rent to a relative at below market rate. Will we be caught for NI or any additional tax?

You will not have to pay NI, but you may have to pay one of the new higher rates of income tax on property – it depends how much the relative is paying, where you are in the UK (the rates do not apply in Scotland), and on whether you have used the reliefs and allowance available to you.

From April 2027, property income will be taxed at a basic rate of 22%, a higher rate of 42% or an additional rate of 47%. You will only need to pay any tax if you have used up your personal allowance on other earnings and if you earn £1,000 a year or more from the property.

If you do earn more than that, you can choose not to pay tax on the first £1,000 or instead, you can deduct some property expenses from the tax calculation (check which apply). If you own the property privately rather than through a company and there is a mortgage on it, you can get income tax relief on the interest payments. Make sure you are doing all of these before you work out the tax.