Fractional CFO for e-commerce software companies

E-commerce software contracts blend platform subscription with payments revenue share, app marketplace economics, transaction fees and merchant services. For the larger platforms, payments and ancillary make up the majority of gross profit, and merchant mix moves gross margin meaningfully.

GMV-driven modelling sits at the centre - take rate, payments penetration and ancillary attach all model off GMV cohorts, and merchant retention curves are built at cohort level rather than aggregated. Pass-through revenue reports net so software economics aren't quietly contaminated by low-margin volume.

Flow provides financial modelling, FP&A and fractional CFO advisory to e-commerce software companies across commerce platforms and storefront builders, headless and composable infrastructure, payments and checkout, post-purchase and logistics, and merchant financial services. We work as the outsourced startup CFO through growth, fundraising and sale processes.

Marcura
Hector
Testim
Panorays
Percepto
Brew
BetterQA
Voereir
TBô
Onlogist
Bonart
Cannadorf
Cannabis Innovation Center
Seagull Maritime
Moburst
Lemonade
Selina
BiomX
Dataprana
Radtonics
Marcura
Hector
Testim
Panorays
Percepto
Brew
BetterQA
Voereir
TBô
Onlogist
Bonart
Cannadorf
Cannabis Innovation Center
Seagull Maritime
Moburst
Lemonade
Selina
BiomX
Dataprana
Radtonics
Marcura
Hector
Testim
Panorays
Percepto
Brew
BetterQA
Voereir
TBô
Onlogist
Bonart
Cannadorf
Cannabis Innovation Center
Seagull Maritime
Moburst
Lemonade
Selina
BiomX
Dataprana
Radtonics

KPIs to track for "e-commerce software" startups

We're very 'KPI-driven' fractional CFOs, and we make sure to monitor the right metrics for your startup.

Subscription ARR

GMV

Payments revenue

Payments penetration

Merchant count

Net merchant retention

ARPU per merchant

App / ancillary revenue

Software gross margin

CAC payback

Financial modelling for "e-commerce software" startups

As fractional CFOs, we build KPI-driven financial models that are insightful and easy to maintain.

Financial modelling is both art and science - models must be robust, but also understandable, and useful for both internal planning and VC fundraising purposes. Hire a fractional CFO who knows how to handle both sides of the equation.

GMV-driven take rate

Take rate, payments penetration and ancillary attach all modelled off GMV cohorts rather than logo cohorts. The merchant who triples GMV is a different revenue trajectory than the merchant who adds three seats, and the model treats them as such.

Payments unit economics

Payments revenue reported net of processor, sponsor bank and interchange with gross margin built from the ground up. Pass-through volume reports net so software economics aren't contaminated by low-margin payments throughput.

Ancillary attach - apps, shipping, capital

App marketplace, shipping, fulfilment and merchant capital revenue reported as distinct expansion paths with their own margin and risk profile. The merchant-financial-services tail is valued differently and needs to be visible separately.

Merchant cohort retention

Cohort retention measured at merchant level by GMV band and segment, with downgrade, plan-tier movement and churn separated. Aggregated retention in this category systematically masks the SMB attrition that drives long-run economics.

Subscription ARR waterfall

Subscription bookings to billings to revenue separated cleanly from GMV-linked revenue and payments. Investors and acquirers can read the software business on its own merits before adding the payments and ancillary stack.

CAC payback by merchant segment

Fully-loaded CAC and payback by SMB, mid-market and enterprise merchant cohorts, with payments-attach lifetime value modelled in. The full unit economics only resolve once payments contribution is included alongside subscription.

Recent fractional CFO track record

See our fractional CFO and financial modelling experience across e-commerce software and beyond.

Simple pricing

No hidden costs, no complicated long-term contracts. We understand how important flexibility is for e-commerce software startups.

Core£4,000

Per month

  • Accounting / FP&A tech stack implementation
  • Monthly financial statements and reporting pack
  • Quarterly board pack with detailed financial analysis (with variance analysis vs. budget, relevant KPI observations etc.)
  • Investor-friendly output
Grow£8,000

Per month

  • Everything in Core, plus
  • Operating model (via an online platform like Runway or Excel-based)
  • Ongoing model maintenance, refining projections, burn/runway management
  • Customer cohorts modelling, churn and retention analysis
  • LTV / CAC, unit economics analysis
  • Cap table management
Pro£12,000

Per month

  • Everything in Grow, plus
  • M&A / fundraising support; review of business plan
  • Pitch deck preparation
  • Investor approach strategy / list building
  • Due diligence support and deal negotiation
  • Valuation as required and free access to Multiples Pro

Packages shown are illustrative, final pricing is tailored to client requirements.

AI & MLFintechConsumer internetDigital mediaE-commerce & marketplacesConsumer productsMobilityDigital healthIndustrial technologyDigital infrastructureIT services

More services

We help you scale by providing fractional CFO advice, through fundraising and a successful M&A exit.

VC fundraising for e-commerce software companies

We help you prepare materials, reach out to investors in our extensive network, negotiate fair term sheets and structure the VC round.

Learn more

M&A for e-commerce software companies

We advise winning tech companies on M&A exits, and over the years successfully executed numerous transactions with both financial and strategic buyers.

Learn more

Talk to us

Schedule a call to get a health check on your business and see how we could help.

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