Taxing a privately bought car.
Discussion
You're overthinking it.
The seller doesn't 'untax' the car. When the transfer of registration is completed and received by the DVLA, the tax the seller is paying/has paid, stops. If they are entitled to any refund, this is then done.
You tax the car immediately using the green new registered keeper slip.
Works well for our wonderful government because 99% of the time, they will receive 2 payments for the month of transfer. They only refund full complete months and back date any new tax to the start of the month.
The seller doesn't 'untax' the car. When the transfer of registration is completed and received by the DVLA, the tax the seller is paying/has paid, stops. If they are entitled to any refund, this is then done.
You tax the car immediately using the green new registered keeper slip.
Works well for our wonderful government because 99% of the time, they will receive 2 payments for the month of transfer. They only refund full complete months and back date any new tax to the start of the month.

Edited by Lincsls1 on Wednesday 6th August 20:58
Lincsls1 said:
MitchT said:
OK, so I tax it online and the seller sends off the change of owner bit and gets a refund on their remaining tax for the year.
I see what you're saying too... I acquire the car on the 9th so we'll both have paid for August tax!
Correct. I see what you're saying too... I acquire the car on the 9th so we'll both have paid for August tax!

Once you've done that then you can tax it using the code on the green slip on the V5.
You will then get a new V5 in 5-7 days max & the seller will get a note saying they are no longer the registered keeper & separately, a cheque for any road tax refund due.
The system is indeed rigged. If a car is sold mid-month the Gov't gets 13 months road tax out of it for that year because you have to tax it from the start of the month in which you buy it & the seller only gets refunded for whole months unused.
If the seller gives you an hour or two to get home before doing the change of keeper online, you don't need to. Or, which happened to me, the seller bizarrely insisted on posting the V5c off. Thanks, 3 days tax at least.
If it's untaxed (from a trader) or SORN though, you do need to buy it straight away, just in case.
Annoyingly, you can't declare a car SORN with the new keeper slip, only buy VED. You can't do this until the change of keeper has been done online. But after a couple of days, the new keeper slip is invalid for SORN because a new V5c has been issued, so it's a narrow window.
I don't mind buying it if it's only the first week of the month.

Annoyingly, you can't declare a car SORN with the new keeper slip, only buy VED. You can't do this until the change of keeper has been done online. But after a couple of days, the new keeper slip is invalid for SORN because a new V5c has been issued, so it's a narrow window.

I don't mind buying it if it's only the first week of the month.
It should be easy enough...
I'm actually buying my OH's car. She's getting a new car and I want something cheap to use as a stop gap until the one I want comes up for sale. We both win 'cause it means I get to buy a really cheap old car that I won't take a big hit on when I part ex it against the one I want and, unlike most old, cheap cars, I can trust it as I know how it's been treated for the last 15 years. She gets a bit more for it than the dealer would have given her in part ex against her new car. Win! Win!
So, whatever the best way is to change the ownership and me to tax it can be sorted sat on the sofa together on Saturday.
I'm actually buying my OH's car. She's getting a new car and I want something cheap to use as a stop gap until the one I want comes up for sale. We both win 'cause it means I get to buy a really cheap old car that I won't take a big hit on when I part ex it against the one I want and, unlike most old, cheap cars, I can trust it as I know how it's been treated for the last 15 years. She gets a bit more for it than the dealer would have given her in part ex against her new car. Win! Win!
So, whatever the best way is to change the ownership and me to tax it can be sorted sat on the sofa together on Saturday.
If you wan to save an extra month's VED, do the change of keeper online the last day of the month (only available up to 7pm, DVLA database issues). Don't use the car the rest of the day, and buy VED on the next morning using the new keeper slip. A car being 'untaxed' for 12 hours won't be an issue, the DVLA database often takes longer than that to update. Or, you could change keeper, and register it SORN and not use it until September? A long wait....
I bought a car on 29th May at a classic auction that was still taxed, and the auction house didn't do a change of keeper until about 2nd June (but backdated it to the auction date of 24th May). The vehicle was therefore 'untaxed' until I received the new V5c. As I mentioned previously, once a new one is issued, you can't make it SORN using the new keeper slip. I recorded it SORN when the V5c arrived, the car was untaxed for about a week, May had already been paid for anyway.
As an existing registered keeper, you can buy VED online on the last day of the month to start the next morning if it is SORN, I did it on 31st July.
I'm fairly sure that you can't so it with the new keeper slip though, for obvious reasons, you're 'supposed' to buy it straight away.
I bought a car on 29th May at a classic auction that was still taxed, and the auction house didn't do a change of keeper until about 2nd June (but backdated it to the auction date of 24th May). The vehicle was therefore 'untaxed' until I received the new V5c. As I mentioned previously, once a new one is issued, you can't make it SORN using the new keeper slip. I recorded it SORN when the V5c arrived, the car was untaxed for about a week, May had already been paid for anyway.

As an existing registered keeper, you can buy VED online on the last day of the month to start the next morning if it is SORN, I did it on 31st July.

paul_c123 said:
Change of registered keeper won't cancel tax bought using the V5C/2 (new keeper slip) or its 12 digit reference number.
Eh? Yes it does, automatically, when DVLA process it. You only use this section if you post it off anyway. The 12 digit number is on Section 6, and incidentally, it is the same 11 digits as the front on the V5c with an extra one at the front. 
Edited by sixor8 on Thursday 7th August 08:04
sixor8 said:
paul_c123 said:
Change of registered keeper won't cancel tax bought using the V5C/2 (new keeper slip) or its 12 digit reference number.
Eh? Yes it does, automatically, when DVLA process it. You only use this section if you post it off anyway. The 12 digit number is on Section 6, and incidentally, it is the same 11 digits as the front on the V5c with an extra one at the front. 
Edited by sixor8 on Thursday 7th August 08:04
He is saying that if the new buyer taxes using the green slip, this won't be cancelled by the seller completing the change of registered keeper.
MitchT said:
It should be easy enough...
I'm actually buying my OH's car.
Random thought, but if you are buying from your OH is there any point changing the registered keeper (and adding another one to the car’s history)? You can still create a bill of sale etc to transfer ownership.I'm actually buying my OH's car.
Chris
For reasons I won't bore you with I'd rather update the registered keeper. I don't think another RK will be an issue. It's a 20 year old E87 BMW 120d with 100k miles on it. There are grazes on every corner, early signs of corrosion on the subframe and she lost the service book years ago so the only record we have of servicing is printouts of recent work and the knowledge in our minds (but no tangible proof) that it's always been done properly prior to those.
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