Who offers the best guarantee? The fine print worth checking before you buy

A manufacturer guarantee is often an afterthought - it's only when something goes wrong with a product that you'll consider how to solve the problem.

But factoring this into a purchase consideration can save you significant time and hassle, and we've found big differences between guarantee periods in our analysis of over 2,000 products.

Find out which household appliance and tech brands offer you the longest guarantee periods, and what to do to make sure you're making the most of them.

Use Which? to help you narrow down your shortlist

Which? reviews provide a rigorous and impartial assessment of product's performance, but we also include important need-to-know information that you'll want to factor into a purchase. We've collected guarantee details on dozens of different brands, so you can pick a product that gives you that extra peace of mind.

Check the tech specs of our reviews in the following categories, where we've included information on how long a manufacturer guarantee lasts, and important need-to-know information.

Mattresses - from one year to a lifetime guarantee

A mattress is a long-term investment that should offer you many years of comfort, but some brands aren't willing to put their weight behind the quality of a product for more than a year. Here are some examples of how much differ brand guarantees can differ.

• One year - Argos only offers a one year manufacturers guarantee as standard for its range of Argos Home products.
• 10 years - Emma, Eve and Casper all offer a 10 year guarantee, though you'll need to purchase direct through their website, or an authorised retailer. Casper now sells into the UK from mattressonline.co.uk.
• 25 years - Ikea is confident enough in the quality of its products to offer a free 25 year guarantee against defects in materials and workmanship that covers many of its mattresses and bed bases.
• Lifetime - unusually, some mattress brands offer lifetime guarantees. DreamCloud says its products will be free from defects in workmanship and materials for as long as you own and use it.

Use our mattress reviews to check the manufacturer guarantee before you buy.

Vacuum cleaners - from one to five years

Corded and cordless vacuum cleaners have lots of moving parts, so it's fair to assume you'll have a few issues to deal with over the lifetime of the product. Brands vary here in the guarantee periods they offer - and there are important terms and conditions to bear in mind, too.

• One year - Hoover only offers a one year guarantee on its corded and cordless models
• Five years - by contrast, Shark will give you five years - one year as standard, and if you register your purchase within 28 days on the Shark website, it'll extend this by an additional four years. However, the guarantee only covers the battery for the first two years.

Our cordless vacuum cleaner reviews and corded vacuum cleaner reviews reveal how long a manufacturer guarantees the product.

Home appliances - from one to five years or more

Home appliances like washing machines, fridge freezers, and built-in ovens are expected to last - and these are some of the most common products where you're likely to be pressured into purchasing extended warranty cover to help resolve problems down the line. With some brands offering far longer guarantee periods from the off, you'll want to take this into account for additional peace of mind.

• One year - Indesit's appliances guarantee only protects you against faults and defects for a year. This can vary however - its washing machines benefit from a 10 year parts guarantee if you register the appliance.
• Five years - Hisense and Samsung fridge freezers include a two year guarantee as standard, though some products are eligible for an additional three years at no extra cost.

You'll find guarantee information in our reviews for the following home and kitchen appliances:

• Washing machine reviews
• Tumble dryer reviews
• Dishwasher reviews
• Fridge Freezer reviews
• Built-in oven reviews
• Coffee machine reviews

Tech products - usually one or two years

When it comes to technology and smart products, you're less likely to see manufacturer guarantees that differ widely from brand to brand.

When it comes to TVs and mobile phones, all brands offer either one or two years as standard.

For this reason it's a good idea to consider the retailer guarantee when purchasing a tech product in particular.

Our TV reviews,mobile phone reviews and sound bar reviews all include manufacturer guarantee information to help you make the right choice.

Are retailer guarantees better than manufacturer guarantees?

You might find that the retailer you're shopping at offers a longer guarantee than that provided by the manufacturer. This can be particularly beneficial for products with typically short periods, like tech items. Here are some examples:

Richer sounds - the popular electronics retailer offers a six year guarantee on its TVs and projectors, covering full parts and labour. It'll also collect and return your TV (for models 39-inch and over) and if it can't repair it, it'll give you vouchers to spend on a replacement.

John Lewis - famous for its free guarantee period that often extends beyond that offered by the manufacturer, John Lewis will give you a two year guarantee on all electricals, and five years on TVs.

Lakeland - the popular homewares store also sells a range of electricals, including coffee machines, vacuum cleaners, and kitchen appliances. You'll benefit from a three year guarantee for any product you buy from Lakeland - allowing you to return it for a refund or replacement if you have the receipt or emailed order confirmation.

You might be tempted by an extended warranty on offer from a retailer - but don't be too hasty. Read our guide to extended warranties before you take the plunge.

How to make a guarantee claim when something goes wrong

You'd hope that trying to resolve a fault with a product that's still within its guarantee period is straightforward, but this may not always be the case.

It's usually more straightforward to make a faulty goods complaint under the Consumer Rights Act if your purchase has developed a fault within the first six months. In this instance, you'll want to contact the retailer, rather than the manufacturer, to resolve the issue.

After this period, the onus is on you to prove the product is faulty. If the manufacturer or retailer has a good guarantee, that might make the issue fairly simple to resolve, and underlines the importance of a good manufacturer guarantee period that extends past the first year.

For more information, read our guide on when to use a manufacturer guarantee.