Warning: Planning a day out? Third-party ticket sites often miss big discounts for families, students, carers and more

Third-party sites – including platforms such as Booking.com, GetYourGuide, Viator and others (see full list) – can be useful for discovering nearby activities and attractions, and comparing your options. But use them to book tickets and you could end up paying more than you need to.

We looked at 22 attractions across nine cities in England, Scotland and Wales, to see what discounts or concessions they offered, and how often these were available through third-party sites. Here's what we found:

Concession tickets are often MUCH cheaper

The exact discount you can get depends on the specific attraction and your circumstances, but to give you an idea, here are just a few of the dozens of examples we spotted (correct as of Tuesday 27 October):

• Tower of London: Carers go completely FREE when booking direct. But one third-party site didn't include ANY concessions for carers. What's worse, the same site also charged more than DOUBLE the usual price for an adult ticket, meaning a carer could end up spending a whopping £84.50 more than needed.

• Techniquest Science & Discovery Centre, Cardiff: Carers go FREE when booking direct here as well, but one third-party site we checked didn't list any relevant concessions. It means a carer could pay £15.45 for an adult ticket despite not needing one.

• National Football Museum, Manchester: A family of four (two adults and two children, or one adult and three children) can get a bundle for £44 when booking directly – but would have to shell out up to £60 in total on individual tickets via another third-party site we saw, losing out on £16.

• SS Great Britain, Bristol: Infants aged zero to three go FREE – but yet another third-party site didn't list this concession, meaning parents could end up paying £14.50 for a ticket if booking through it.

• Scottish Football Museum, Glasgow: Also offers FREE entry to children under five – but one third-party didn't list this, instead offering child tickets covering "age 17 and younger" for £10.60 each.

How to save on days out

Before booking a paid attraction, remember that there are HUNDREDS of completely FREE museums and attractions to visit across the UK – see our Free UK museums and galleries guide for a list of 200+.

But if you're after tickets to a paid day out, be sure to check via the attraction's DIRECT website in the first instance – even if the third-party listing you've got your eye on looks like a great deal. Keep in mind that because of sponsored search results across search engines, you may need to scroll a bit further down to find the direct listing.

Keep an eye out for 'add-ons' too – sometimes, third-party listings advertise extras, such as audio guides or guided tours, as added benefits for booking with them, even though you'd ALSO get these with a ticket you'd purchase directly. Always evaluate whether add-ons are worth the price to you and your family.

Plus, check out our regularly-updated Cheap days out and Free & cheap things to do with kids pages for the latest deals and discounts.

What did the third-party sellers say?

We contacted 18 third-party ticket sellers, raising specific listings we identified which either did NOT offer concessions when they were offered directly, or had tickets listed for MORE than they cost when booking direct – or a combination of the two. Here's what they told us:

• Booking.com, Expedia, and GetYourGuide told us that ticket suppliers are generally responsible for setting their own prices – including discounts and promotions – which then appear to customers on site. A spokesperson from Booking.com added that prices can differ between its app and desktop site, while a spokesperson from GetYourGuide said it "regularly deactivates activities or supply partners" that don't follow local ticketing regulations.

• In addition to the above, Guruwalk, Headout, and Lovetovisit ALSO told us that the listings we flagged have now been addressed, whether that was putting listings under review, having their prices reconfirmed with ticketing partners, or updating them with seasonal pricing and additional concessions.

• Virgin Experience Days declined to comment.

• We also contacted Attractiontix, Days Out with the Kids, Feel the City, Golden Tours, Holibob, Picniq, Tiqets, Tripadvisor, Trip.com, Viator, and VisitLondon, but haven't yet heard back – we'll update this story if that changes.