Ask ten people what their event budget is and most will give you a single number. That number is usually the amount they'd be comfortable spending — not a plan for how to spend it. The gap between those two things is where events go over.

A budget that holds does three things: it allocates by percentage before it allocates by preference, it names the invisible costs up front, and it keeps a real contingency that nobody is allowed to spend early.

Start with the split, not the wish list

Before you look at a single venue, divide your total into rough proportions. For a standard corporate function — drinks, food, some entertainment, a few hours — this is a reliable starting point:

  • Venue and hire: 30–35%. Room hire, furniture, any minimum spend.
  • Food and beverage: 30–40%. Usually the single biggest line, and the one guests judge hardest.
  • Entertainment and AV: 10–15%. Music, sound, lighting, screens, a microphone that works.
  • Styling and extras: 5–10%. Flowers, signage, printing, keepsakes.
  • Staffing and management: 10–15%. Coordination, service staff, security if required.
  • Contingency: 10%. Not optional. More on this below.

These are starting proportions, not rules. A launch event where the room needs to look extraordinary will pull from food into styling. A long-service dinner will do the opposite. The point of starting with percentages is that when one line grows, you can immediately see which other line has to shrink.

If you can't say what a decision is coming out of, you haven't got a budget. You've got a number and some hope.

The five line items that quietly blow it

In our experience these are the costs people forget, in roughly the order they hurt:

1. Beverages on consumption

A package price per head is predictable. "On consumption" is not, and it is almost always more than expected — particularly for a two-hour window at the start of an evening when everyone arrives thirsty at once. If you go on consumption, set a bar limit with the venue in writing and nominate one person who gets told when it's reached.

2. Staff overtime and extended hire

Events run long. Wonderful for guests, expensive for you: venue hire past the contracted hour, staff on penalty rates, and a pack-down crew being paid to wait. Decide in advance what a one-hour extension costs and whether you'll authorise it.

3. AV that wasn't in the room hire

"The venue has AV" can mean anything from a full rig with a technician to a projector in a cupboard. Ask specifically: is there a technician on site, is it included, and what happens if a laptop won't connect?

4. Dietary requirements handled late

Catering an extra fifteen alternate meals ordered two days out costs significantly more than ordering them with the original numbers. Collect dietaries with the RSVP, not the week of.

5. Delivery, bump-in and bump-out

Flowers, furniture, print and hire items usually have a delivery and collection fee, sometimes with a surcharge for after-hours or weekend access. It's rarely large individually. Across six suppliers it adds up to real money.

Build the contingency properly

A 10% contingency is standard advice, and it's right — but only if it's held rather than allocated. The failure mode is predictable: the contingency exists on the spreadsheet, someone finds a better band in week three, and the contingency becomes the band. Then the actual contingency need arrives in week eight and there's nothing left.

Two rules keep it honest. First, the contingency is not spendable until two weeks out, at which point most surprises have surfaced. Second, one named person approves any draw from it. If that person is also the one who wants the better band, this doesn't work — which is a good argument for the approver being someone with no emotional stake in the styling.

Price per head, then sanity-check the total

Once you have a draft budget, divide it by your guest count. That per-head number is the fastest way to know whether your plan is realistic, because it's comparable across events in a way that totals aren't.

It also makes the effect of guest numbers obvious. Adding twenty people to a 60-person event doesn't add a third to your costs — food and drink scale, but venue hire, AV, entertainment and management largely don't. This is why a slightly larger guest list is often better value per head, and why cutting numbers to save money saves less than people expect.

Get quotes in the same format

Three catering quotes are only comparable if they cover the same thing. Before you send an enquiry, write down: guest number, service style, number of items, staffing, equipment hire, delivery, and whether GST is included. Send that identical brief to everyone.

You'd be surprised how often the "cheapest" quote is cheapest because it quietly excludes staff, or is priced ex-GST while the others aren't. Comparing like with like takes twenty minutes and regularly saves thousands.

A worked example

Say you've got $24,000 for an 80-person evening function. The split might look like this:

  • Venue and hire — $7,500 (31%)
  • Food and beverage — $8,800 (37%)
  • Entertainment and AV — $2,900 (12%)
  • Styling, print and extras — $1,400 (6%)
  • Staffing and coordination — $1,000 (4%)
  • Contingency — $2,400 (10%)

That's $300 per head all in, or $270 excluding contingency. Now when the venue you love comes in at $9,000, you can see immediately that $1,500 has to come from somewhere — and you're making a deliberate trade rather than discovering the problem in October.

The short version

Allocate by percentage first. Name the invisible costs before they arrive. Hold the contingency until two weeks out. Check your per-head number early. Brief every supplier identically.

Do those five things and your budget will hold — not because nothing goes wrong, but because you'll have decided in advance what happens when it does.

Planning something and want a second pair of eyes on the numbers? Send us the details or call 0493 191 530. The first conversation is free, and we'll tell you honestly whether your budget matches your plan.