Adding a Director to a Limited Company BTL Mortgage – What I Learned by Getting the Admin Wrong
Adding a director to a limited company BTL mortgage was something I assumed would be straightforward. It wasn’t. In January the rate on our BTL was sitting at 4.24%. Our broker flagged it as a window worth watching. His read was right, but I held out for lower, and lower never came. By the time I acted we were looking at 4.99%, and that’s where we’ve stayed.
That’s the first lesson: in a market that isn’t moving in your favour, a good rate is worth taking. Waiting for a great one can cost you.
But the rate story isn’t really what this article is about.
Some Context First
I set up our property limited company two years before any of this happened. I did the viewings, managed the small refurb, sourced the furnishings, handled the bookkeeping and annual submissions. My husband was the sole named director at the point of purchase, mortgage advice at the time was that a single employed director would access better rates and a wider pool of lenders, particularly as I was on a career break looking after our baby and not drawing a salary. It was a practical decision, not a reflection of who was actually running things.
After two years of running it invisibly, I wanted to exist on paper.
The immediate reason was specific: to join the residents’ management company for the building our flat sits in, I needed to be a named director of the leasehold company. That required being a director of our property company first. Simple enough on the surface.
What I underestimated was how it would interact with the mortgage.
The Mistake That Put Us in Breach
Adding a new director to a limited company that holds a mortgaged property is a material change to the borrowing entity. Most lenders require you to notify them and obtain consent before you make that change – it’s written into the mortgage conditions. I hadn’t read that part carefully enough. I filed at Companies House first.
That put us in breach.
On top of that, I was rushing the filing. I added my 50% shareholding but forgot to simultaneously reduce my husband’s from 100% to 50%. Companies House accepted the submission without question. Our lender noticed the filing showed 150% total shareholding and flagged it immediately.
Two problems, one avoidable if I’d slowed down.
What Fixing It Actually Involved
The Companies House error was straightforward, amend the filing, resubmit, done. The lender process was more involved.
To formally approve the structural change, our lender required:
- A written application to consent to the new director and shareholder
- An administration fee of £150
- A Deed of Guarantee, a legal document making me personally liable as guarantor for the mortgage
- Independent legal advice, a solicitor had to certify they’d explained the Deed to me, that I understood it, and that I was signing freely
That last point is worth understanding properly. Independent legal advice here doesn’t mean a lengthy consultation. It means a solicitor reviews the document with you, explains your obligations, and signs a certificate confirming they’ve done so before witnessing your signature. I used an online solicitor service, straightforward, and considerably cheaper than a high street appointment. The fee for the witnessing and certification was £150. Combined with the lender’s administration fee, the process cost £300 in total.
The lender sent the Deed of Guarantee by post. I arranged the solicitor appointment, signed in their presence, and posted it back in the prepaid envelope provided. The confirmation letter arrived in February.
Both of us now correctly listed as directors, shareholders at 50% each, and guarantors. Breach resolved.
The Timing
Our fixed term was ending at the end of March. I was in Lapland on a child-free trip with a friend in the middle of March. Sorting a lender breach from inside the Arctic Circle is not something I’d recommend. We got there, just. But the margin was tighter than I’d have liked.
What the Companies House Filing Actually Involves
Since rushing this is what caused the problem, it’s worth walking through clearly.
When you appoint a new director (form AP01 for an individual), you’re recording their name, date of birth, nationality, and correspondence address. Straightforward. Where people trip up is the shareholding and the Persons with Significant Control register.
If the new director is also becoming a shareholder:
- Issue new shares or transfer existing ones using a stock transfer form
- Update the PSC register to reflect who now holds significant control and in what proportion
- Make sure the total shareholding adds up to 100% after every change
Do all of this in one sitting. Check your numbers before you submit. Companies House will accept almost any filing – they are not checking your maths.
And before you touch any of it: read your mortgage conditions and contact your lender.
Where It Left Us
The rate we’d been holding out for never came. We’re at 4.99% and the property covers its own costs, mortgage, insurance, maintenance, with not much to spare. We have good tenants and we want to keep them, which means being realistic about what we can ask for and flexible when circumstances change. The real running costs of the property are broken down here.
There’s no cushion right now for major works or an unexpected void. That’s the honest position. The property is holding its value and housing people well, that’s enough for this stage. But it’s also why getting the admin right matters. When margins are tight, an avoidable mistake that costs time, money, or a lender relationship is one you really feel.
What I’d Do Differently
Read the mortgage conditions before filing anything at Companies House. Contact the lender first, get consent in writing, then make the change. Slow down on the filing itself and check every shareholding figure before submitting – the total must equal 100%.
If you’re becoming a guarantor, understand what you’re signing. A Deed of Guarantee is not a formality. It makes you personally liable. The independent legal advice requirement exists precisely because it’s serious.
None of this is complicated. But it rewards being methodical in a way that, this time, I wasn’t.
This article reflects my personal experience managing a BTL property through a limited company. It’s for general information only – if you’re making changes to a company structure or mortgage, speak to a broker or solicitor who can advise on your specific situation.
