Startups > Simon Merchant

Simon Merchant

Flagstone helps savers maximize interest by accessing 200+ accounts from 65+ banks on one platform.

Private Equity $191M total Founded 2013 London, England 251 employees

Flagstone is a UK-based fintech platform that aggregates 200+ savings accounts from 65+ banks into a single dashboard, allowing individual savers, SMEs, and charities to diversify deposits and maximize interest returns without paying management fees. The platform addresses post-financial-crisis gaps: declining rates, heightened bank risk sensitivity, and the administrative burden of managing multiple accounts. Flagstone takes a share of interest (up to 0.30%) rather than charging fees, and has facilitated £5 billion in deposits across 725,000 customers managing £17 billion in assets.

Problem solved

Savers lack a simple way to diversify bank deposits across institutions while managing multiple accounts and finding competitive rates without administrative friction.

Target customer

Individual savers (minimum £10,000), SMEs (minimum £50,000), charities (minimum £250,000), and wealth management firms seeking white-label deposit solutions.

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Founders

Simon Merchant

Co-Founder (former CEO, transitioned to board 2026)

10 years as investment banker at Morgan Stanley; founded and sold market-leading fintech firm StreamVPN to US public company in 2005; Oxford graduate with PE and media investment experience.

Andrew Thatcher

Co-Founder & Executive Director

15 years in banking and hedge funds at Merrill Lynch, Citigroup, GLG Partners (Principal, Co-Head of UK), and MAN Group (Executive Director, Asia).

Arman Tahmassebi

CEO (appointed January 2026)

Seasoned fintech operations leader with 25+ years experience; 5-year tenure as COO at LendInvest.

Funding history

Early funding Unknown November 29, 2017 Led by Unknown · Unknown

Mid-stage Unknown Unknown Led by WealthClub, Volution · Unknown

Series C/D £108M March 2024 Led by Estancia Capital Partners · Unknown

Series D $137.6M November 1, 2024 Led by Unknown · Estancia Capital Management, Volution Ventures, Alexander Square Partners, Kindred Capital, MONY Group, OMERS Ventures, Moneysupermarket Group

Total raised: $191M

Industries

Financial Services Real Estate Banking

Pricing

No management or administration fees. Flagstone receives up to 0.30% of interest earned on each savings account opened. Rates displayed are net of Flagstone's share. Minimum deposit £10,000 for individual/joint accounts; £50,000 (individuals), £100,000 (businesses), £250,000 (charities) for adviser/professional tier.

Notable customers

St. James's Place, Revolut, Saga, individual savers (725,000+), SMEs, charities

Integrations

St. James's Place, Revolut, Saga, white-label partnerships with financial advisers and FinTech platforms

Tech stack

OWL Carousel (JavaScript libraries) LazySizes (JavaScript libraries) jQuery (JavaScript libraries) core-js (JavaScript libraries) Bootstrap (UI frameworks) Vimeo (Video players) Salesforce Service Cloud (Live chat) Zendesk (Documentation) Popper LottieFiles PWA Open Graph Linkedin Insight Tag (Analytics) Hotjar (Analytics) Heap (Analytics) Google Call Conversion Tracking (Analytics) Google Analytics (Analytics) Facebook Pixel (Analytics) HSTS (Security) Font Awesome (Font scripts) Microsoft 365 (Email) Cloudflare (CDN) cdnjs (CDN) Salesforce Marketing Cloud Account Engagement (Marketing automation) Twitter Ads (Advertising) Microsoft Advertising (Advertising) theTradeDesk (Advertising) Google Tag Manager (Tag managers) Salesforce (CRM) Azure (PaaS) DigiCert (SSL/TLS certificate authorities) AB Tasty (A/B Testing) Movable Ink (Personalisation)

Website

flagstoneim.com/

Competitors

Raisin

Operates across multiple European countries with $304M+ funding; Flagstone is UK-focused but dominates UK market with 725,000 customers and £17bn AUA.

TotallyMoney

Focuses on credit comparison; Flagstone specializes in deposit aggregation and savings optimization.

MoneySuperMarket

Broader financial comparison platform; Flagstone provides integrated deposit management across 65+ banks.

Insignis Cash Solutions

Targets businesses and charities; Flagstone serves broader customer segments with more consumer-focused distribution.

Akoni Cash Management

Serves SMEs and organizations; Flagstone's consumer base is larger with more technology-first approach.

Why this matters: Flagstone has scaled to 725,000 customers managing £17bn in assets and turned profitable in Q4 2022—rare for a fintech born in 2013—while competing against well-funded European players like Raisin. Its £108M+ funding in 2024 and white-label partnerships with major platforms (Revolut, St. James's Place, Saga) signal strong B2B2C traction in a market where deposit aggregation remains fragmented.

Best for: Individual savers, wealth management firms, and financial advisers who need to offer clients access to competitive savings rates across multiple banks without building integrations or paying management fees.

Use cases

High-net-worth portfolio diversification

A retiree with £500,000 in savings uses Flagstone to spread deposits across 5-7 accounts from different banks to maximize FSCS protection (£85,000 per bank) and capture the highest rates available. This solves the problem of managing multiple logins and missing rate increases.

SME cash management

A growing consultancy with £200,000 in operating cash needs to optimize returns without taking investment risk. Flagstone's adviser tier lets their accountant access 200+ accounts and automatically reinvest maturing deposits, reducing manual work from hours to minutes.

White-label wealth management integration

A wealth manager like St. James's Place embeds Flagstone into their platform to offer clients deposit optimization as a core service, improving client retention and generating recurring revenue from interest share without building in-house aggregation infrastructure.

Charity endowment management

A mid-sized charity needs to generate returns on a £1M endowment while maintaining liquidity for grant-making. Flagstone's charity tier lets trustees access insured accounts across 65+ banks and reinvest seven times per year to capture rate movements.

Alternatives

Raisin Choose Raisin for multi-country European expansion; Flagstone dominates UK with deeper bank relationships and consumer traction.

Traditional wealth advisers Choose traditional advisers for holistic portfolio management; Flagstone is best for pure deposit optimization and self-directed savers.

Direct bank relationships Direct banking eliminates intermediaries but requires managing dozens of logins and missing rate changes; Flagstone centralizes discovery and switching.

FAQ

What does Flagstone do? +

Flagstone aggregates 200+ savings accounts from 65+ banks into a single platform with one login, allowing customers to diversify deposits, maximize interest returns, and reduce bank risk. Customers can manage multiple accounts and reinvest automatically without paying management fees; Flagstone earns up to 0.30% of the interest earned.

How much does Flagstone cost? +

Flagstone charges no administration or management fees. Instead, Flagstone takes a share of the interest (up to 0.30%) on each account opened. Rates displayed are net of Flagstone's fee. Minimum deposit is £10,000 for individuals/joint accounts; £50,000-£250,000 for adviser/professional tiers depending on customer type.

What are alternatives to Flagstone? +

Raisin (multi-country European competitor with more funding), TotallyMoney (credit-focused comparison), MoneySuperMarket (broad financial comparison), Insignis Cash Solutions and Akoni Cash Management (niche SME/charity focus). Direct bank relationships avoid intermediaries but lack Flagstone's central rate discovery and switching automation.

Who uses Flagstone? +

Individual savers (725,000+ customers), wealth management firms (St. James's Place, Saga via white-label), SMEs, charities, and financial advisers. Average customer opens 5 accounts and reinvests 7 times per year, indicating active asset management.

How does Flagstone compare to Raisin? +

Raisin operates across multiple European countries and has raised $304M+ across 11 rounds, giving it broader reach. Flagstone is UK-focused but dominates the UK market with 725,000 customers managing £17bn in assets, deeper bank partnerships (65+ vs Raisin's scope), and achieved profitability in Q4 2022. Flagstone is better for UK-centric customers; Raisin for European expansion.

Is Flagstone safe? +

Flagstone does not hold customer deposits directly. Deposits are held with 65+ partner banks, each protected by FSCS (Financial Services Compensation Scheme) up to £85,000 per bank per customer. Flagstone's role is aggregation and rate discovery only, reducing counterparty risk.

Can businesses and charities use Flagstone? +

Yes. Flagstone offers a professional adviser tier for businesses (£100,000 minimum) and charities (£250,000 minimum), allowing trustees and accountants to manage deposits across multiple accounts with higher minimums and dedicated support.