Retainer portfolio margin · agencies & marketing services

You Don’t Lose a Retainer’s Margin in One Bad Month. You Lose It 20 Minutes at a Time.

A quick call that was not in scope. A “small” extra version of the banner. A revision round nobody logged. Each one is too small to invoice and too frequent to absorb, and by the end of the quarter one of your retainers is being delivered at a loss while another quietly pays for it. This shows you which one, how much it costs you every month, and the exact fee it needs to be.

Buy Now — $19

One-time payment · works offline · nothing leaves your browser

Whole book
every retainer in one view
blended margin, not one client at a time
The fee it needs
repricing solver per client
plus the hour cut that does the same job
$19
once, for the planner and every re-run
no seats, no subscription, no account

The arithmetic that makes a healthy-looking retainer unprofitable

Two numbers do almost all the damage, and neither appears on the invoice. The first is scope creep: the unbilled hours you absorb because refusing them feels worse than eating them. The second is utilisation: the share of a paid hour that actually reaches client work. Price a retainer as though your team is 100% billable and you have priced a fantasy.

  • Scope creep is a margin multiplier, not a rounding error — published agency worked examples put a 30% target margin at roughly 19.5% at +15% creep, 12.5% at +25%, and about 2% at +40%. The fee never moved; the hours did.
  • Over half of projects run into scope creep at all, with average cost overruns around 27% — which is why the average retainer, not the unlucky one, is the one to check.
  • Delivery staff run 65–85% billable at best, and agency-wide net utilisation sits nearer 50–60%. A $75 loaded hour at 75% utilisation really costs $100 to put on a client.
Aggregate erosion of roughly 5–10 points of agency profit across a year

Benchmarks above are published agency-industry figures included as orientation for your own inputs, not a guarantee of your numbers. Every figure this tool produces is derived from the fully-loaded costs, hours and creep percentages you enter yourself.

The free calculators answer one client. Your problem is eleven.

Every agency blog has a scope-creep calculator that takes one project, returns one number, and asks for your email. None of them hold a portfolio — and “is this retainer profitable?” is not the question an owner actually has.

1

True cost, not the rate card

Every role carries a fully-loaded cost per hour and a billable-utilisation percentage, defaulting into the healthy 65–85% band. Hours are inflated by the creep you actually absorb and deflated by the utilisation you actually achieve, so the delivery cost on screen is the one that hits your bank account — not the optimistic one in the proposal.

2

Ten clients, readable at a glance

Each retainer shows gross margin in dollars and percent, your effective realised hourly rate against the one you think you charge, and the hour count where margin hits zero. A traffic light bands it healthy above 55%, thin 30–55%, underwater below 30% — so a book of ten resolves in about five seconds, not an afternoon in a spreadsheet.

3

The number to put in the email

For any client below your target the solver gives the exact monthly fee that reaches it (fee = cost ÷ (1 − target margin)), and alongside it the alternative: the hours you would have to stop delivering to get there without raising the price at all. Two defensible options, both costed, before you open the conversation.

4

How much creep the book survives

One slider re-runs the whole portfolio at +10, +20 and +40% unbilled hours and tells you the creep level at which blended margin breaks through your target, and the level where portfolio profit reaches zero. It also names which clients subsidise which, in cash, every month.

What it looks like

A three-client book mid-review. The blend says 43%, but the blend is not the story — one client is being delivered at a loss and one is paying for it.

Portfolio — 3 retainers, $22,200 a month
Target margin 55% · default utilisation 75%
43.3%
Blended margin
1
Underwater
LOSING MONEY: Vellum & Co. $259 a month of delivery cost above the fee. At a 55% target it needs $7,687 a month, against $3,200 today.
RetainerFeeTrue costEffective rateNeedsMargin
Harbourline Dental Group52 hrs scoped · 8% creep absorbed $12,500 $5,406 $222.58 56.8%
Northstar Logistics34 hrs scoped · 18% creep absorbed $6,500 $3,718 $162.01 $8,261 42.8%
Vellum & Co.29 hrs scoped · 35% creep absorbed $3,200 $3,459 $81.74 $7,687 −8.1%
Vellum is the instructive row. It is the smallest fee on the book and the one nobody worries about — but it absorbs 35% creep against a 29-hour scope, so the realised rate is $81.74 an hour when the headline rate looks like $110.34. It does not need a nudge; at a 55% target it needs to be a $7,687 retainer, or a 29-hour scope cut to 12. Harbourline’s $7,094 of margin is what has been quietly covering it.

Your options today are agency management software priced per seat for a team that already has an operations lead, or a spreadsheet that treats every paid hour as billable. This is the thing in between: a purpose-built portfolio margin planner for the one decision that actually moves the number — for $19, once, before you send the renewal email.

One file. One payment.

Buy it, open it, and have your whole retainer book banded before your next renewal call. No account, no subscription, no seat count.

Retainer Margin Planner
$19
One-time purchase
Yours to keep. No renewal, no per-seat pricing.
  • Unlimited retainers and roles, each with fully-loaded cost and billable utilisation
  • True delivery cost per client, inflated by scope creep and deflated by real utilisation
  • Gross margin in dollars and percent, with healthy / thin / underwater banding
  • Effective realised hourly rate against your headline rate
  • Break-even hour count per retainer
  • Repricing solver: the exact fee for your target margin, plus the hour-cut alternative
  • Portfolio roll-up with blended margin, monthly profit and who subsidises whom
  • Scope-creep stress slider to +60%, with the creep level where the book breaks
  • CSV export of the portfolio table, JSON export and import for backup
  • Installable PWA — works fully offline
  • Light and dark themes, mobile-ready
Buy Now — $19
Instant access after checkout. Runs entirely in your browser — no client names, fees, salaries or hours are ever uploaded.

Before you buy

Does it connect to my time tracker or accounting system?

No, and that is deliberate. It makes no network calls at all, which is why you can put real salaries, real client fees and real margins into it without a procurement conversation. You bring the hours from wherever you already track them; this is where the costing, the banding and the repricing decision live.

I don’t know my fully-loaded cost per hour.

Salary plus employer taxes, benefits, software and a share of overhead, divided by paid hours a year. A rough figure still works: the tool is a comparison across your own book, so even an approximate cost will rank the retainers correctly and show you which conversation to have first. Refine it later and every number updates.

What does utilisation actually change?

It converts a paid hour into a delivered hour. At 75% utilisation an $80 hour costs $106.67 to put on a client, because the other 15 minutes are paid for and not billed. Leave a role blank and it uses your portfolio default; healthy delivery staff sit in the 65–85% band, and anything above that is usually optimism rather than measurement.

Where does the repricing number come from?

The standard rearrangement of the margin formula: fee = cost ÷ (1 − target margin). At a 55% target, a retainer costing $3,459 to deliver needs to be a $7,687 retainer. The tool shows that alongside the alternative that needs no price rise at all — the reduced hour count that reaches the same margin — because one of those two conversations is usually much easier than the other.

Where does my data go?

Nowhere. It is a single HTML file storing everything in your own browser. You will be typing in client names, monthly fees and staff costs, so that matters. Export a JSON backup whenever you want a copy, a CSV of the portfolio table for a board pack, or import a backup to move it to another machine.