A client rings, describes the job, and asks roughly what it will cost. You give them a number. That is a ballpark figure, and there is nothing wrong with it as long as everyone treats it as a conversation starter. The trouble starts when that same number, or something close to it, ends up on a tender with your company name at the bottom.
The gap between a ballpark figure vs tender price is not about how confident you feel. It is about what sits underneath the number. One is a feel for the job. The other is a record of every quantity, every rate and every allowance, built so somebody else can check it.
What a ballpark figure is actually for
A rough number has a real use. It tells a client whether their budget is in the right region before anyone spends money on drawings, and it tells you whether a job is worth chasing at all. Say someone wants a single-storey rear extension and their budget is half of what similar jobs have cost you. A quick figure saves both of you weeks.
What it cannot do is carry risk. It is built from memory, a rough take-off (if there is one at all) and rates that are whatever you last remember paying. Nobody has measured the foundations, counted the openings or read what the specification actually asks for. Fine for a chat. Not fine for a commitment.
Ballpark figure vs tender price: what changes when you submit
Once a number goes in as tender pricing, the client is entitled to hold you to it. Their QS will compare it line by line with the other bids. If you win, it becomes the budget you build to, the base for every valuation and the starting point for every argument about a variation.
A tender price worth submitting is built from a full take-off measured to NRM2, priced against current supplier and labour rates, with preliminaries, overheads and margin added on top rather than guessed at. It comes with a note of what has been included and what has been assumed. So if a client queries a figure, you can point to exactly where it came from.
A ballpark figure answers "roughly how much?". A tender price has to answer "how did you get that?", line by line, months after you wrote it.
What a proper build up includes
Strip a tender price back and it should contain the following. If any of these are missing, you are closer to a ballpark than you think.
- Measured quantities. Every element taken off the current drawings, with a reference back to the drawing it came from, not lifted from an old job.
- Current rates. Labour, plant and materials priced on what they cost now and local to the job, backed by fresh supplier and subcontractor quotes wherever a package is big enough to matter.
- Priced preliminaries. Site set up, welfare, supervision, scaffolding and skips priced against the programme for this job, not a percentage borrowed from the last one.
- Overheads and margin shown separately. So you can see what the job actually costs before you decide what to put on top.
- Written assumptions and exclusions. The list you point to when the scope shifts or someone asks why a figure is what it is.
Where amateur pricing goes wrong
The failure points are the same ones every time. Quantities lifted from an old job without checking they still apply. Rates that have not been touched since the last price rise. Preliminaries added as a flat percentage instead of being priced against the actual programme and site set up.
None of these show up until the job is running and the margin has gone. A flat percentage for prelims looks tidy on paper. Then the job takes longer than the percentage assumed, the scaffold stays up another month, and that money comes straight out of the profit you thought you had.
There is a quieter problem too. A ballpark that slowly turns into a tender price rarely gets rebuilt from scratch. People nudge it instead: add a bit here, take a bit off there to look competitive. By the time it goes in, nobody can say what the number is made of, and every question from the client becomes harder to answer than it should be.
Why it is worth getting someone else to build it
Pricing your own work while also running the site, chasing labour and keeping other jobs moving is how corners get cut on the estimate. You measure the easy bits properly and eyeball the rest. You mean to go back and check the drainage runs, and then the deadline arrives.
A second pair of hands on the take-off and pricing, someone whose only job that day is the numbers, tends to catch what gets missed when you are fitting it in between everything else. It also gives you something a rough figure never does: a document you can hand to the client's QS without worrying about what they will find. If the fee is what holds you back, this piece on why a rough estimate often costs more than a proper one sets out the trade-off honestly.
A simple test before anything goes out
Pick three lines at random from your price and ask where each number came from. If the answer is a drawing reference, a measured quantity and a current rate, you have a tender price. If the answer is "that's about what it was last time", you have a ballpark with a covering letter. Knowing the difference between a ballpark figure vs tender price is simple. Acting on it when the deadline is tomorrow is the hard part.
Keep ballpark figures for early conversations, and say plainly that they are indicative. When the job is real and the number carries your name, build it properly or have it built. That one rule protects more margin than any amount of haggling after the event.