I'm a UK contractor. I'm going to use the word contracting henceforth, but feel free to swap it our for freelancing or consulting, or whatever you think sounds better.
Most companies will want you contracting through a limited company in the UK. The main reason for this is so that the client can sue you if you screw something up. You'll also notice that most companies will ask you have business insurance as well, this again is so that in the event they need to sue you, you're fully covered for it.
The other reason you might need to contract through a limited company or an "umbrella company" these days is because of IR35 regulations. Basically employers can now get screwed by HMRC if they're paying people as contractors who are working in effect as employees. The reason for this regulation is that it's more tax efficient for both you and the client if you work as contractor as you can claim expenses, they don't need to worry about paying you severance / sick pay / etc, and both you and your employer don't need to pay NI contributions on your salary. As you might imagine the government would prefer only the wealthy had access to such privileges so they introduced IR35.
In effect this now means it's too risky for a company to pay an individual for an extended period of time without ensuring things are done correctly. IR35 basically gives companies two options: 1, pay a company for work with no hard requirements on who does the work, the time they do the work, or where they do the work – this is an "outside IR35 contract" and this will require you set up a LLC to contract through. Or 2, pay an umbrella company for the work and that umbrella company will employ you so you can get screwed by the taxman in the same way everyone else does without the benefits of a real employment contract (it's lose, lose) – this is an "inside IR35 contract".
On top of this, companies will often have contracts with recruitment agencies allowing that agency to be the sole recruiter for said company. This means even if they're willing to risk paying you for your services without going through all the IR35 nonsense, they contractually can't because they have agreements in place with recruitment agencies preventing it. I've personally ran into this issue when a client I was contracting for changed their preferred recruitment agency and I was unable to continue contracting with the client without the client first paying off my recruiter due to a non-solicitation clause.
If you want a company to pay you directly (as a self-employed sole trader) you would probably need them to pay you for a product and not for your labour, because if they're paying for labour they need to go through all the regulatory hoops.
Imo there's very little reason to be a contractor in the UK anymore. With all the extra tax headaches, the government constantly finding new ways to screw you and job insecurity, it's honestly not worth it.
Most companies will want you contracting through a limited company in the UK. The main reason for this is so that the client can sue you if you screw something up. You'll also notice that most companies will ask you have business insurance as well, this again is so that in the event they need to sue you, you're fully covered for it.
The other reason you might need to contract through a limited company or an "umbrella company" these days is because of IR35 regulations. Basically employers can now get screwed by HMRC if they're paying people as contractors who are working in effect as employees. The reason for this regulation is that it's more tax efficient for both you and the client if you work as contractor as you can claim expenses, they don't need to worry about paying you severance / sick pay / etc, and both you and your employer don't need to pay NI contributions on your salary. As you might imagine the government would prefer only the wealthy had access to such privileges so they introduced IR35.
In effect this now means it's too risky for a company to pay an individual for an extended period of time without ensuring things are done correctly. IR35 basically gives companies two options: 1, pay a company for work with no hard requirements on who does the work, the time they do the work, or where they do the work – this is an "outside IR35 contract" and this will require you set up a LLC to contract through. Or 2, pay an umbrella company for the work and that umbrella company will employ you so you can get screwed by the taxman in the same way everyone else does without the benefits of a real employment contract (it's lose, lose) – this is an "inside IR35 contract".
On top of this, companies will often have contracts with recruitment agencies allowing that agency to be the sole recruiter for said company. This means even if they're willing to risk paying you for your services without going through all the IR35 nonsense, they contractually can't because they have agreements in place with recruitment agencies preventing it. I've personally ran into this issue when a client I was contracting for changed their preferred recruitment agency and I was unable to continue contracting with the client without the client first paying off my recruiter due to a non-solicitation clause.
If you want a company to pay you directly (as a self-employed sole trader) you would probably need them to pay you for a product and not for your labour, because if they're paying for labour they need to go through all the regulatory hoops.
Imo there's very little reason to be a contractor in the UK anymore. With all the extra tax headaches, the government constantly finding new ways to screw you and job insecurity, it's honestly not worth it.