Birthdays, family & groups

The Cost Of A Birthday Party For 10 To 50 Guests: Budgets With The Age Discount Applied

Budget tables for birthday parties from 12 to 50 guests, with the age-based discount applied and the 5% service charge and 10% VAT included. How the bill is built, and three items people forget.

25/08/2026 · 4 min read · AVATAR KARAOKE

The Cost Of A Birthday Party For 10 To 50 Guests: Budgets With The Age Discount Applied

People asking about the cost of a birthday party usually get a long menu and an hourly room rate, then have to add it up themselves. Even after adding up they are not reassured, because they do not know what else might appear on the bill.

This article does the opposite: it gives the all-inclusive figures directly, for the five most common sizes, and shows exactly how much the age-based discount changes them.

A birthday bill has exactly four parts

The room — charged by the hour, depending on capacity and floor area.
The set menu — all-inclusive or à la carte. A standard set for 10 to 15 guests covers 3 starters, 3 main protein dishes, 3 seafood or meat dishes, 3 rice or noodle dishes, 2 fruit platters and a case of beer.
Additional drinks — kept separate because it varies most.
5% service charge and 10% VAT — calculated on the three above.

A formula for checking any quote yourself:

Total = (room + food + drinks) × 1.155
The factor is 1.155, not 1.15, because VAT is calculated on the amount that already includes the service charge. If a venue hides those two until payment, the problem is not the money but the way they work.

Budgets for five sizes — before any discount

All figures are for a four-hour party, including the 5% service charge and 10% VAT.

Size	Room	Room rate × 4	Set menu	Drinks	All-inclusive total
12 guests	Eva · 40 m²	1,400,000đ	6,500,000đ	500,000đ	9,702,000đ
20 guests	Celestial · 55 m²	2,000,000đ	9,750,000đ	600,000đ	14,264,000đ
30 guests	Luminary · 70 m²	2,600,000đ	13,000,000đ	800,000đ	18,942,000đ
35 guests	Nebula · 80 m²	3,000,000đ	16,250,000đ	1,000,000đ	23,389,000đ
50 guests	MINIBAR · 110 m²	3,400,000đ	22,750,000đ	1,200,000đ	31,589,000đ

One thing worth noticing: the larger the party, the lower the cost per head, because the room is shared among more people. If you are weighing two small parties against one combined one, the figures point clearly to combining.

How much the age discount changes the figure

Avatar runs the programme where your age is your percentage off the room rate. Three rules to get right:

It applies to the room rate only — not to the set menu, not to the drinks.
It does not stack with the 30% off the room rate from 12pm to 10pm, Sunday to Thursday. Choose one, whichever is worth more.
It is applied before the 5% service charge and 10% VAT.

Here are the figures for each size.

12 guests · Eva

Age	Off the room rate	Total payable	Saving	% of the whole bill
No offer	0đ	9,702,000đ	—	—
35	490,000đ	9,136,000đ	566,000đ	5.8%
45	630,000đ	8,974,000đ	728,000đ	7.5%
60	840,000đ	8,732,000đ	970,000đ	10.0%
70	980,000đ	8,570,000đ	1,132,000đ	11.7%

20 guests · Celestial

Age	Off the room rate	Total payable	Saving	% of the whole bill
No offer	0đ	14,264,000đ	—	—
40	800,000đ	13,340,000đ	924,000đ	6.5%
50	1,000,000đ	13,109,000đ	1,155,000đ	8.1%
60	1,200,000đ	12,878,000đ	1,386,000đ	9.7%

30 guests · Luminary

Age	Off the room rate	Total payable	Saving	% of the whole bill
No offer	0đ	18,942,000đ	—	—
45	1,170,000đ	17,591,000đ	1,351,000đ	7.1%
50	1,300,000đ	17,441,000đ	1,502,000đ	7.9%
55	1,430,000đ	17,290,000đ	1,652,000đ	8.7%

35 guests · Nebula — usually a milestone celebration

Age	Off the room rate	Total payable	Saving	% of the whole bill
No offer	0đ	23,389,000đ	—	—
70	2,100,000đ	20,963,000đ	2,426,000đ	10.4%
80	2,400,000đ	20,617,000đ	2,772,000đ	11.9%

50 guests · MINIBAR

Age	Off the room rate	Total payable	Saving	% of the whole bill
No offer	0đ	31,589,000đ	—	—
45	1,530,000đ	29,822,000đ	1,767,000đ	5.6%
50	1,700,000đ	29,626,000đ	1,964,000đ	6.2%

Looking at all five tables together shows a pattern: the real saving on the total bill sits between 6% and 12%, highest for older celebrants and for parties where the room is a larger share of the bill relative to the food. The percentage in the programme's name always sounds larger than the real saving, and knowing that in advance lets you budget accurately rather than feel let down at payment.

The detailed method for each room class, and the comparison with the time-slot offer, are in how the birthday age discount is calculated.

Three items people forget when budgeting

Extra hours. A party planned for four hours very often runs to five. Budget for one spare hour rather than being caught out.
Cake and flowers. Usually bought elsewhere, not part of the venue's quote, and usually the line left out of the spreadsheet.
Drinks beyond the estimate. The most variable item. The simple control is to agree a quantity with the group in advance and ask staff to let you know when it is close.

Two ways to optimise the budget without lowering the standard

Take whichever offer is worth more. Since the two do not stack, the break-even sits at 30: under 30, the 12pm–10pm window Sunday to Thursday wins; over 30, the birthday offer always wins, and by more with every year.
Combine rather than split. One party of 30 costs less per head than two of 15, because the room is paid for once.

A checklist for reading a quote

Does the quote state the room name, floor area and capacity?
Is there one all-inclusive figure with the 5% and 10% included, or only a menu to add up?
Is the age-based discount shown as its own line?
Are the deposit and cancellation terms in writing, by message or email?
What happens if the actual head count is 20% lower than expected?
Are VAT invoices issued, and how far in advance are the details needed?

See the all-inclusive set menus for what a set contains, and the VIP room list to match floor area against your guest count.

Avatar Karaoke — premium karaoke in District 1, open since 2010

An all-inclusive quote within 30 minutes: one figure with the 5% service charge and 10% VAT already in it — not a menu for you to add up.

Your age is your percentage off the room rate · VAT invoices · Written booking confirmation · Free car parking.

63–65 Pham Viet Chanh, Cau Ong Lanh ward (formerly District 1) · Hotline 0915.03.1111

Get an all-inclusive quote within 30 minutes · how the birthday age discount works · all-inclusive set menus