This doesn't necessarily mean getting a second job. In fact - so long as you have a broadband connection - there are numerous ways to make money online without leaving the comfort of your home. We've rounded up some top examples.
Do I need to pay tax on 'side hustle' income? Since 2017 Brits have benefited from a £1,000 'trading allowance' whereby it's possible to each earn up to £1,000 a year tax-free from 'side hustles' such as flogging items on eBay or making money from online surveys. If you earn more than this from online extras, you'll need to register as self-employed with HMRC and pay tax on your profits. Money you earn on investments such as dividends is taxed separately - this article explains how.
There are websites that will pay you for your opinion on anything from the latest hit TV show to shampoo or dog food. To get started, sign up to survey sites such as i-Say (previously Ipsos), Swagbucks, YouGov and Opinion Outpost. Once you're a member, they'll send you details of surveys you're eligible for and how much they pay.
Focus groups are more in depth and usually mean attending a session in person. They can pay well though - up to £100 for an hour or two. Takepartinresearch.co.uk or Paidfocusgroups.co.uk are good places to start.
These virtual currencies are notoriously volatile as well as being the subject of various scams - check out Trust No one: The Hunt For The Crypto King on Netflix for a story about how it can all go horribly wrong.
If you live near a train station, football stadium or city centre, it's possible to generate a regular income stream from renting out your off-street parking space. You can rent out your space on an hourly, daily, weekly or even monthly basis.
You can list your parking space on sites such as JustPark, ParkLet, Your Parking Space and Park On My Drive. Fee structures vary but usually include commission on the booking, plus some sites may also charge a listing fee.
You have to liaise with the driver making the booking, including providing directions where necessary and ensuring that access is kept clear. You may also need to check whether suitable liability cover is included in your home insurance.
Making purchases via cash-back websites can add up to several hundred pounds a year. You sign up to a cash-back site such as Topcashback or Quidco and search for the online retailer or company you're looking to buy from. If the company is listed, you click on the link to take you to their website which tracks your visit. You then complete the purchase as normal.
The first step is to sign up and enter details of your skills and experience, after which you're able to 'bid' for freelance work posted by clients. It's a good idea to look at the rates offered for projects to get a feel for the appropriate price level to bid at (if it's not a fixed price).
You may be required to submit evidence of your work, or undergo an interview, at which point you're told whether or not you are successful. In some cases, clients may contact you directly to invite you to bid for their work.
The freelance website is responsible for making the payment, although they may take a commission or charge a fee for their services. You can also build up your profile by asking clients to submit feedback on completed jobs.
Trainers have moved from functional footwear to coveted fashion accessories, fuelled by companies such as Nike and Adidas releasing limited edition styles. These have a high resale value, however, the challenge is getting your hands on them in the first place.
Those willing to commit the time and resources follow the big retailers, such as Nike and Footlocker, to find out the time and date of release of the most sought-after styles. The process varies from entering into a raffle for the opportunity to buy a pair (in a certain size) to calling up at the right time to reserve a pair for collection.
By way of example, the Nike Air Jordan 4 White and Black trainers sold for £180 when released, and were being resold at around £300 on eBay. Some sizes (typically men's 8–11) are more popular than others.
However, you have to factor in the cost of selling fees, delivery and the need for the trainers to be inspected by eBay's authenticators before despatch. You should also establish the likely demand for the trainers, before purchase, to avoid being stuck with expensive stock.
If you've got a good eye for photos, you could try your hand at stock photography. Image library websites like iStock and Getty Images allow users to upload photos and earn a small royalty when they're used.
Remember, if your photos include other people or their property, you'll need to get the person or owner to sign a model release form. This form, which you can find easily online, is written permission for the photographer to use the images they take of a person or property for commercial purposes. Certain websites will not accept uploads unless you have a model release.
Stock photos are put to a huge variety of uses, so the possibilities are endless. It will take some initial time and effort to build a profitable library of images, but once you do you'll have a stream of passive income.
Typical services offered include 30 to 60 minute walks, drop-in visits and house sittings or 'doggie day care' and 'dog boarding' in your home. While there may be a guide rate, sitters and owners are free to negotiate their own prices.
Online property rental marketplaces such as Airbnb and VRBO have become increasingly popular in recent years. They allow property owners to rent out spaces for people looking for a place to stay, from single rooms to whole properties.
There are a number of other issues to consider when renting property, including the terms of your mortgage and house insurance policy, whether permission is needed from the freeholder (if applicable) and specialist insurance requirements.
Etsy provides a marketplace for people to sell their hand-made and other items, so may appeal to people looking to combine their hobby with making money. However, it takes a little longer to set up than selling on eBay as you have to create a shop and ensure that each product has a comprehensive description and good quality photos.
Etsy charges a listing fee of $0.20 (£0.16) per item, together with a 6.5% transaction fee and a 4% + £0.20 payment processing fee. You can also pay Etsy to advertise your products more widely on the internet.
With a little effort, you can turn a love of writing into extra monthly income. Many bloggers need some extra help producing content for their site, and pay freelancers to cover a particular topic. You could try pitching ideas to your favourite bloggers, or use a freelancing website such as People Per Hour to pitch for listed jobs and advertise your services.
One such site is Bumblebee Auctions, which is used by the Metropolitan, Devon and Cornwall, Suffolk, Durham and Hertfordshire police forces amongst others. Items vary from jewellery, bikes, cameras, tools and computers. The downside is that you may have to collect the item, although delivery can be added at an extra charge for some items.
You can list your flat or house as a potential location for filming photo shoots. You don't have to live in a mansion, in fact, there's good demand for more 'gritty' properties. However, your odds are improved if you live in, or near to, London and you have good parking available.
You may have watched one of the extreme couponing US shows where shoppers reduce the price of their shop from $300 to $10 by cashing in a fistful of coupons. However, there is a more moderate approach to couponing if you don't want a queue full of people breathing down your neck at the check-out.
Many of the large supermarkets have loyalty schemes which are often app-based. Waitrose customers can choose from a range of different vouchers every week on its app, giving money off selected products. The Tesco Clubcard app has a similar scheme, including bonus points and double points coupons which can be redeemed against future shops or partner rewards.
Or, if you're willing to sign up to a monthly commitment, the Tesco Clubcard Plus Scheme allows customers to get a 10% discount on two shops per month (up to £20 each time), for a cost of £7.99 a month.
Alternatively, apps such as Shopmium, provide cashback if you buy selected products from a range of retailers, including Tesco, Sainsbury's, Asda, Morrisons and Waitrose. You buy the product first, then scan your receipt and product barcode to receive the cashback via PayPal or bank transfer.
Most domain names sell for a few quid - but there are some which change hands for millions of pounds. Domain flipping is when you buy a domain name as cheaply as possible then sell it for more than you originally paid for it.
Most of us like to upgrade our smartphones and other devices whenever a shiny new one comes out. This means that, across the UK, there are countless drawers and cupboards containing old smartphones, cameras, and games consoles.
It's not just celebs making money from Instagram - 'micro influencers' are normal folk who make cash creating and sharing content. The key to success is building a large, engaged and enthusiastic following who will react to your social media posts with likes, shares and comments.
Most social media influencers start off by collaborating with brands by plugging and picturing their products (which they usually receive for free) before graduating to getting paid cold hard cash for product posts on Instagram and Facebook.
Radio stations, in particular, regularly give away five-figures sums of money in competitions you can enter with just a quick text. Other typical prizes include cars, holidays, tech products, kitchen appliances, gig tickets and… just about anything.
Pro compers enter hundreds of competitions each week which they find by subscribing to Compers News or Theprizefinder.com. Before you get started, set up a separate email address just for competitions - otherwise your email index will get swamped with spam and newsletters.
Selling items on eBay and Facebook is so last year - now it's all about dropshipping, which is a 'fulfilment method' used by retail businesses. Dropshippers buy goods from a third party and then have these goods shipped directly to customers. Crucially, you don't need to buy, or physically hold, any stock.
Next, you need to set up a shop on Shopify or account on eBay and find buyers - perhaps using ads on Facebook or Instagram. You advertise the product at a higher price than you're buying it for - this mark-up will be your profit.