As an example, let's say a friend of yours is selling their car, and they also need some DIY work doing on their house. If you do the DIY work for them, and they give you the car as payment, do you need to pay tax on this?
If the transaction is one that would attract tax if settled by cash, it attracts tax if settled by barter.
For example, a private person selling their second hand car is not a taxable transaction. If done by a second hand car business it is. Similarly, a mate doing some DIY for you is not taxable in your hands. A mate who’s business it is to do DIY work (e.g. a builder or other tradesperson) doing work on your business premises is different.
However, if it is clearly a transaction when something of value is traded for something of commensurate value then tax is payable. Where it gets murky is in a situation of reciprocal gift giving.