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ACF Investors

acfinvestors.com · Sheffield, UK

“ACF Investors co-invests alongside experienced syndicates of sector-smart angel investors to fund and scale early-stage UK businesses across most sectors, aligning capital, sharing due diligence, and providing ongoing post-investment support.”

$100K – $1M
Check Size
Leads & Follows
Lead Tendency
$100M
AUM
3+ Months
Timeline
01Investment Thesis

ACF Investors co-invests alongside experienced syndicates of sector-smart angel investors to fund and scale early-stage UK businesses across most sectors, aligning capital, sharing due diligence, and providing ongoing post-investment support.

Exclusion Criteria

No income-generating investments (capital growth focus only); requires a committed angel syndicate with a lead investor meeting minimum commitment thresholds (£40K-£70K); UK-based businesses only.

02Investment Team
TM
Tim Mills
Managing Partner
SF
Sam Fennell
Partner
PF
Paul Fauset
Partner
GW
George Whitehead
Partner
SA
Sina Ataherian
Investment Director
LB
Liam Bradley
Associate
MB
Matt Boreman
Associate
03F4 Research Brief

ACF Investors Research

Investment Thesis

ACF Investors (formerly the Angel CoFund) is a UK venture capital co-investment platform founded in 2011 by Tim Mills, formerly Investment Director at the British Business Bank. The firm manages a £100M+ programme (all figures in GBP) across two co-investment vehicles, the Angel CoFund and the Delta Fund, that partner with experienced syndicates of sector-focused angel investors to fund and scale early-stage UK businesses. Rather than sourcing and pricing deals independently, ACF aligns its capital with angels who are already committing meaningful personal capital and sector expertise to a round, shares due diligence with that syndicate, agrees investment terms alongside them, and provides ongoing post-investment support. The firm explicitly seeks capital growth rather than income-generating investments and typically invests via the same or an aligned share class as the other round participants, avoiding special terms.

Sector Focus

ACF is explicitly generalist ("most sectors") but its live portfolio clusters into six categories it uses on its own site: CleanTech, Consumer and Creative, DeepTech, FinTech, Medtech, and Software/Digital Transformation. Representative sub-themes include: fintech infrastructure and payments (Ebury, Form3, BMLL, Bancone, NorthRow, OTCX), medtech and diagnostics (Creo Medical, Neurovalens, Cipher Surgical, Sky Medical, Oxford Medical Simulation, Cumulus Neuroscience), climate/cleantech (Tevva, Limejump, Enval, Smile Plastics, Sonichem), deep tech/hardware (Blu Wireless, Wayland Additive, Keit), consumer and creative (Gousto, Vitl, Hopster, Reboxed), and B2B software (BaseKit, Huq Industries, Techspert.io, HR DataHub, Sonicjobs, Venuescanner).

Stage Focus

ACF invests at the early stage, typically alongside a priced seed or Series A round led by an angel syndicate. Minimum total round sizes are £200K (Angel CoFund) and £500K (Delta Fund).

Check Size

  • Angel CoFund: £100K-£1M per round, targeting roughly 30% of the round (up to a 49% cap in some cases)
  • Delta Fund: £200K-£1M per round, capped at 30% of the round
  • Lead angel minimum commitment: £40K (Angel CoFund) or £70K with deep sector expertise (Delta Fund)

Lead Tendency

Mixed. ACF is structurally a co-investor that matches capital to an angel-led round, so the lead investor of record is typically an angel or syndicate rather than ACF itself. In practice, however, press coverage sometimes credits ACF as having "led" a round (e.g., Hammer Missions, OneID) when its co-investment ticket was the largest institutional check. Classified here as "both."

Recent Activity

ACF has been actively deploying through 2025:

  • April 2025: Co-invested £1.4M seed round in Hammer Missions (AI drone building-inspection software), alongside angel investors including Graham Hunter (GeoSLAM) and Martin Grant (Atkins), to fund North American expansion.
  • February 2025: Led/co-invested in a £16M round (ACF's own ticket reported around £1M) in OneID, a UK bank-verified digital identity provider used by NatWest and Adobe.
  • July 2025: Participated (£300K) in a £3.25M round in Cumulus Neuroscience (at-home EEG tech for neuroscience clinical trials), led by WhiteRock Capital Partners.
  • September 2025: Participated in a £4.8M round in NoBACZ Healthcare, a Cambridge spinout building patented "liquid bandage" wound-care technology for livestock and horses, led by The Yield Lab.
  • October 2025: Portfolio company BMLL Technologies (capital markets historical order-book data and analytics) was acquired by Nordic Capital for approximately $250M, marking one of ACF's largest recent exits.

Fund status: actively deploying, with multiple new investments and one notable exit in the second half of 2025.

Portfolio Highlights

ACF's portfolio spans 90+ companies with 16 recorded exits. Notable names and outcomes:

  • BMLL Technologies - acquired by Nordic Capital (Oct 2025, ~$250M)
  • Cavalry - acquired by Canva
  • FATMAP - acquired by Strava
  • Ebury - international payments and FX, raised at a £550M+ valuation
  • Form3 - cloud-native payments infrastructure, raised a $220M Series C
  • Gousto - recipe-box delivery, ranked on the FT Growth Champions list
  • Limejump - energy flexibility platform, exited
  • Neurovalens - neurostimulation wearables with FDA approvals
  • Non Linear Dynamics, LivingLens, Sophia, IMSPEX Diagnostics, Vantage Power, Syrinix, City Pantry - additional exits

Team

  • Tim Mills, Managing Partner - Founded ACF in 2011; previously Investment Director at the British Business Bank
  • Sam Fennell, Partner
  • Paul Fauset, Partner
  • George Whitehead, Partner
  • Sina Ataherian, Investment Director
  • Liam Bradley, Associate
  • Matt Boreman, Associate

Decision Process

ACF operates as a partnership rather than a solo-GP or formal investment-committee shop. Because its model requires an already-committed angel syndicate as a precondition, its own internal process is layered on top of syndicate due diligence: it reviews the syndicate's due diligence, negotiates aligned terms, and makes a partnership-level go/no-go decision. Typical time from initial meeting to completed investment is around three months, with the Delta Fund sometimes moving faster given the stronger commercial validation required of its leads.

Founder Preferences

ACF looks for UK-based, early-stage founders who have already assembled a credible syndicate of sector-smart angel backers willing to commit meaningful personal capital (minimum £40K-£70K from the lead). It favours founders across a broad range of sectors rather than a single vertical thesis, with a bias toward businesses seeking capital growth rather than income, and a preference for standard, non-preferential share terms shared with other round participants.

Geographic Focus

United Kingdom only. ACF is headquartered in Sheffield (Cooper Buildings, Arundel Street) with a second office in London (Farringdon), and its capital comes in part via a relationship with the British Business Bank.

04Selected Portfolio
Biotech & Life Sciences
Neurovalens·Cumulus Neuroscience·Small Pharma·NoBACZ Healthcare
Climate & Sustainability
Limejump
E-commerce & Marketplaces
Gousto·Venuescanner
Enterprise Software
BaseKit·De-Ice·Autologyx·Huq Industries·Hammer Missions·Cavalry·Blu Wireless
Fintech & Payments
Ebury·Form3·BMLL
Food & Beverage
Vitl·Bancone·City Pantry
Healthcare & Digital Health
Creo Medical·Techspert.io·Micrima
HR Tech & Future of Work
Sonicjobs·HR DataHub
Insurance
Konsileo
Manufacturing & Industrial
Tevva·Wayland Additive Limited
Media & Entertainment
Fatmap
Other
OneID
Open the full portfolio→
05Recent Updates

Fresh signals from public announcements, essays, and portfolio activity.

See full activity (5) →
Portfolio company BMLL Technologies, a capital markets historical trading data and analytics provider, was acquired by Nordic Capital for approximately $250M.
EXIT·bmlltech.com+1
OCT 27, 2025
Participated in a £4.8M round for NoBACZ Healthcare, a Cambridge spinout commercialising patented liquid-bandage wound-care technology for livestock and horses.
INVESTMENT·acfinvestors.com+1
SEP 2025
Participated with a £300K ticket in Cumulus Neuroscience’s £3.25M round for at-home EEG technology for clinical trials, led by WhiteRock Capital Partners.
INVESTMENT·tech.eu
JUL 8, 2025
Co-invested in Hammer Missions’ £1.4M seed round to expand its AI drone building-inspection platform into North America.
INVESTMENT·businesscloud.co.uk+1
APR 17, 2025
Led/co-invested in a funding round for OneID, a UK bank-verified digital identity verification provider used by NatWest and Adobe.
INVESTMENT·tech.eu+1
FEB 13, 2025
06Frequent co-investors
CC
Committed Capital
Both backed 2 of the same companies
Konsileo, De-Ice
IC
IQ Capital
Both backed 2 of the same companies
BMLL, Neurovalens
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Quick Reference
Check Size
$100K – $1M
Stages
Seed · Series A
AUM
$100M
Decision
Partnership · 3+ Months
Involvement
Board Observer
Location
Sheffield, UK
Sector Focus
Fintech & PaymentsConsumer Apps & SocialBiotech & Life SciencesSemiconductors & HardwareClimate & SustainabilityEnterprise SoftwareMedia & EntertainmentHealthcare & Digital Health
Models
B2B SaaSConsumerMedTech DevicesFinTech Infrastructure
Technology
Hardware
See all Fintech & Payments investors →See all Consumer Apps & Social investors →See all Biotech & Life Sciences investors →
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Focus Areas
Fintech & PaymentsConsumer Apps & SocialBiotech & Life SciencesSemiconductors & HardwareClimate & SustainabilityEnterprise SoftwareMedia & EntertainmentHealthcare & Digital Health

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F4 Intelligence Report · Last Researched August 28, 2026F4 Research Engine