How should eco founders brief a fractional CMO without buying an agency in disguise?

Quick answer

Brief a fractional CMO as a decision owner: channel mix, claims freeze, vendor map, and a 90-day scorecard the board can read. They should not be a media buyer with a CMO title. Timing (when to hire at all) lives in the first marketer guide. How to pick an execution shop lives in the agency guide.

FTE vs agency vs this brief

GuideJob
First marketerWhen to add marketing headcount at all
Choose agencyHow to vet execution partners
This guideWhat to put in the fractional CMO SOW, scorecard, and kill rules

When a fractional CMO fits

  • Founder is the bottleneck on decisions (budget, claims, vendors), not only on making ads
  • You have or will hire specialists (email, paid, creative) who need a single brief
  • Board or investors want a marketing owner who is not a junior generalist
  • You are not ready for a $180K+ full-time CMO and do not want an agency to set strategy by default

Skip fractional CMO if product-market fit is still a guess, or if you only need someone to click around Ads Manager. Use the first-hire signals first.

In scope vs out of scope

They ownThey do not own
Channel mix and test budget vs the CAC floorDaily bid changes as the only job
Vendor map (agency, UGC, retail media) and who fires whomBecoming a hidden second agency
Claim freeze with the substantiation ownerWriting unscoped “eco” lines to hit ROAS
90-day scorecard and board narrativeVanity dashboards with no contribution
Hiring plan for the next FTEIndefinite hours with no succession

Hours are typically 1 to 2 days a week. Write the day split: strategy, reviews, founder 1:1. If they need 5 days, you are hiring a FTE and calling it fractional.

What the brief must contain

  1. Economics: contribution, CAC payback, LTV band; see healthy CAC
  2. Claim kit: must / may / must not plus who signs ads; pair with substantiation folder
  3. Stack: live channels, agencies, tools, and what is broken (tracking, email, Amazon)
  4. Decisions reserved for founder: pricing, new markets, brand name, litigation
  5. 90-day outcomes: 3 to 5 measurable jobs, not “fix marketing”
  6. Kill / extend: date and criteria before the first invoice

90-day scorecard (board-readable)

MetricWhy the board cares
Blended contribution and payback, not platform ROAS aloneCash
New-customer mix vs harvestingGrowth quality
Claim or policy incidents on live ads and CSEco-specific risk
Vendor list with owners and spendNo shadow retainers
One documented test (creative, incrementality, or channel)They are steering, not decorating

If they cannot explain incrementality vs last-click, they are not a CMO. Method: incrementality testing.

Red flags in the first month

  • They rewrite the homepage to “more eco” without the claim kit
  • They insist on taking over the ad account as the only proof of value
  • No written decision log; everything lives in Slack
  • They will not name what they will stop (channels, agencies, vanity campaigns)
  • Guaranteed ROAS or “we will 3x you” in the pitch

Handoff to FTE or agency

The job is to make the next hire cheaper: a ranked backlog, a claims owner, and a vendor map. If after two quarters you still cannot describe what the CMO decided, you bought meetings. Convert to FTE, switch to a scoped agency, or stop.

Strategy is a seat, not a retainer shape

If the person cannot say no to a channel, they are not a CMO. They are extra hands.

Frequently asked questions

How should eco founders brief a fractional CMO?

Write economics, claim kit, vendor map, reserved founder decisions, 90-day outcomes, and a kill date. Hire them to own decisions, not to be a media buyer.

Fractional CMO or agency first?

Fractional CMO when you need a brain to brief vendors. Agency first when the founder already sets strategy and only needs execution. Do not let the agency set claims and mix by default.

How many hours is enough?

Usually 1 to 2 days a week with a written split. Five days is a FTE. A few hours of “advice” with no scorecard is a coffee chat.

What should the board see?

Contribution and payback, new-customer mix, claim incidents, vendors, and one real test. Not follower counts or unscoped impact stories.

When do we replace them with a full-time CMO?

When daily ownership is cheaper in-house and the fractional lead has left a backlog and a claims system. Do not hire a FTE just to duplicate the same meetings.