The person behind Lumi
Lumi Accountancy is a one-to-one chartered practice in Winchester. You deal directly with Chris Sullivan ACA — an ICAEW Chartered Accountant — not a call centre and not a different junior every quarter.
Who is behind Lumi Accountancy?
Lumi Accountancy is run by Chris Sullivan ACA, an ICAEW Chartered Accountant (member no. C011009337) and the firm's founder. It's a one-to-one chartered practice at Abbey Mill in Winchester: every client deals directly with Chris, and every credential — ICAEW, Companies House, Xero — can be independently verified.
Last reviewed August 2026
Out with one of the unofficial Lumi mascots.
Chris Sullivan ACA
Hi, I'm Chris. I started Lumi because I genuinely believe accountancy should feel less like a chore and more like having someone in your corner who you can ask questions without judgement, with no topics off limits.
I've spent over seven years in the industry, working across audit, accountancy, personal and corporate tax, and supporting businesses through acquisitions and sales. I love the variety; no two clients are the same, and I find that genuinely energising.
What I can't stand? The kind of accountant who files your return, takes their fee, and disappears until next year. That's not Lumi. We're here when you need us.
When I'm not waist-deep in spreadsheets, you'll find me walking Chip and Link (my two dachshunds), cheering on Southampton at St Mary's, or playing football — usually until I get injured.
How to check we are who we say we are
Anyone can call themselves an accountant. "Chartered Accountant" is a protected title. Every claim below is independently verifiable — the links go to the official registers, not to us.
| Credential | Reference | Where to verify it |
|---|---|---|
| ICAEW Chartered Accountant (ACA) | Member no. C011009337 | Lumi on the ICAEW directory |
| Registered company | Lumi Accountancy Limited, no. 17052646 | Companies House |
| Xero Certified Advisor | Bronze Partner | Lumi on the Xero advisor directory |
| Hampshire Chamber of Commerce | Member | Hampshire Chamber member directory |
| Saints Foundation | Corporate Patron | Saints Foundation |
Registered office: Abbey Mill, Abbey Mill Gardens, Winchester, Hampshire, SO23 9LH. Registered in England & Wales. As an ICAEW member I'm bound by the ICAEW Code of Ethics and subject to the institute's practice assurance and complaints procedures.
What working with Lumi actually looks like
Who will I actually deal with?
Chris, every time. You get one qualified Chartered Accountant who knows your business, not a rotating team and not an offshore processing centre. On the Complete package that includes unlimited phone support.
Are you qualified to give tax advice?
Yes. ACA is the ICAEW's chartered qualification — three years of exams plus supervised practical experience, and ongoing CPD. It's a protected title and membership can be checked on the ICAEW register.
Do you only work with Winchester businesses?
No. Most work happens through Xero, email and video calls, so location isn't a barrier — we work with clients across Hampshire and the wider UK. If you'd rather meet in person, the office is at Abbey Mill in Winchester.
How big a business do you work with?
From newly incorporated companies through to around £10m turnover. Below that we're a good fit; well above it you'd be better served by a larger firm with a bigger team, and we'll say so.
Have a proper conversation before you commit
A free 30-minute call, no obligation. If we're not the right fit we'll tell you honestly and point you somewhere better.