UK - Closing Down a Limited Company

A 10-second Google brought me to this advice (full disclosure, the advice is from a company advertising paid-for company administrative services, but in this case you don't seem to need their services):

If you are closing your company by way of strike off, then you will be responsible for ensuring this is done correctly. All outstanding liabilities of the company should be dealt with and any assets you want to take from the company should be done before you submit the strike off application. You should note that any assets remaining in the company after it has been dissolved will become ‘bona vacantia’ and ownership will pass to the Crown.

Strike off is achieved by completing a DS01 form and submitting this to Companies House. The DS01 form can be completed online directly with Companies House. You must also ensure that any interested parties such as shareholders or outstanding creditors are sent a copy of this too. Your intention to dissolve the company will be advertised in the Gazette, and so long as no objections are received, the company will be struck off the register after a period of three months.

The DS01 link takes you to the appropriate Government portal for managing companies, applicable to public limited companies, private limited companies, or limited liability partnerships.

I've completed the DS01 process a number of times in my past work as a financial controller.

In your case sounds like it will be very simple:

• No need to worry about filing accounts, as long as you are up to date Companies House will allow you to strike off the entity at any time.
• You can file online for a small fee.
• Companies House will publish a notice in the Gazette for two months to see if anyone objects.
• Assuming no one does, then you'll receive a notice of dissolution.

One final note, empty your bank account as a loan repayment before starting the process as any remaining assets become the property of the crown as part of this process.