In eight hours, a finance manager who arrives convinced their costing is “good enough” usually leaves with a list of three or four products, clients, or service lines they have been quietly subsidising for years. That shift — from believing the numbers to interrogating them — is what our TDABC workshop is built to produce. This is what participants actually walk away with after a single day.
How to turn a messy P&L into a working cost model
Most attendees come in with a profit and loss statement that tells them the company made money last year and almost nothing about where that money came from or leaked away. The first part of the workshop is hands-on translation: taking real cost categories — salaries, depreciation, rent, software, logistics — and grouping them into resource pools that map to how the business actually operates.
Participants learn to separate the cost of capacity from the cost of activity. A department that costs €500,000 a year and has the practical capacity to handle 8,000 hours of work has a capacity cost rate of roughly €62.50 per hour. That single number, which almost nobody calculates before the workshop, becomes the foundation for everything that follows.
Why time equations beat endless interviews
The classic objection to activity-based costing is that it takes months of interviews and surveys to build, and it is obsolete the moment it is finished. Time-Driven ABC removes that bottleneck. Instead of asking staff what percentage of their time they spend on each task, you estimate how long each activity takes and let the model do the arithmetic.
In the workshop, participants build their first time equation live: a base time for a standard transaction, plus increments for the things that make some transactions more expensive — an urgent order, a non-standard configuration, a new customer who needs hand-holding. By lunch, most people have a working equation for one of their own processes and can see immediately how complexity drives cost.
Where your real margins are hiding
The afternoon is where the room goes quiet. Once a model is running, participants apply it to their own customer or product data and build a whale curve — cumulative profit plotted from most to least profitable. Almost every time, the curve climbs well above 100% of total profit before a long tail of unprofitable accounts drags it back down.
This is the moment the workshop is designed for. A client that looks healthy on revenue can be deeply unprofitable once you load in the cost to serve them: the small orders, the returns, the custom requests, the slow payments. Participants leave able to point at specific accounts and say, with evidence, “this one is costing us money.”
How to act on what the model tells you
Insight without action is just an interesting chart. The final block focuses on decisions: which loss-making customers to reprice, which to re-serve through a cheaper channel, and which to let go. We work through the difference between cutting a cost and removing the demand that drives it — because firing a customer does not automatically remove the capacity you were using to serve them.
Participants also learn how to present this to a board or a sceptical colleague. A whale curve is persuasive precisely because it is built from the company’s own numbers, not from a benchmark or a consultant’s assumption.
What you do not need before you start
The most common reason businesses delay a costing project is the belief that they need perfect data first. The workshop dismantles that. You do not need a new ERP, a data warehouse, or a year of clean records. You need approximate capacity figures, a reasonable estimate of activity times, and the willingness to refine as you go. A rough model that points in the right direction beats a perfect model that never gets built.
That is the real takeaway after eight hours: profitability visibility is not a software purchase or a multi-month consulting engagement. It is a way of thinking that you can start applying on Monday morning.
Want to experience it yourself? Our next online TDABC workshop runs on 30 June and 1 July 2026. It is hands-on, you build a model with your own logic, and you leave with a method you can use immediately. See the upcoming workshops and register here.