Prosecco math has a trap in it: the answer changes completely depending on how it's being served. A bottle poured as full glasses covers five people once. The same bottle poured as toast flutes covers six or seven. Poured into spritzes, it covers eight. Hosts who use the wrong divisor either run out mid-toast or discover a case of unopened bottles the next morning.
The three divisors
| How it's served | Pour | Serves per 750 ml bottle |
|---|---|---|
| Full glass (dinner, party) | 150 ml | 5 |
| Toast flute | 100–120 ml | 6–7 |
| Aperol/Hugo spritz | 90 ml | 8 |
| Mimosa (with juice) | 90 ml | 8 |
Toast math
One toast round needs guests ÷ 6 bottles. For 60 guests that's 10 bottles; for 120, 20 bottles. Two practical notes from every wedding bartender ever: pour flutes no more than 10 minutes before the toast or the bubbles are gone by the speech, and add one spare bottle per 30 guests for spillage and top-ups. So a 60-guest toast is really 12 bottles, not 10.
Party math
When prosecco is the drink (a brunch, a shower, an aperitivo hour), plan the standard 2-drinks-first-hour rule from the alcohol formula and divide by 5. Thirty guests for two hours = 90 glasses = 18 bottles. When it shares the bar with beer and cocktails, prosecco typically takes 25–35% of total drinks.
Mimosa brunch math
Mimosas are two-thirds prosecco, one-third orange juice in a 135 ml build. A bottle stretches to 8 mimosas; a litre of juice covers 22. For a 20-person brunch at 2.5 mimosas each: 50 mimosas → 7 bottles of prosecco and 3 litres of juice. Cheaper prosecco is correct here — juice erases the difference between a $12 bottle and a $25 one.
Spritz math
At 90 ml per drink, prosecco goes further in spritzes than any other serve — but it brings a liqueur bill with it. The spritz calculator does the full three-ingredient math, and this guide covers the Aperol side.
Which prosecco to buy
For toasts and mimosas: the cheapest DOC bottle you don't find embarrassing — it's on stage for eight seconds. For drinking straight: DOC or DOCG "brut" (drier) over "extra dry" (confusingly, sweeter). Buying by the case usually saves 10–15%, and chilled stock matters more than label prestige: warm good prosecco loses to cold average prosecco every single time. Budget 3–4 hours of fridge time, or 20 minutes in an ice-water-salt bath per the ice guide.
Quick reference
| Scenario | Bottles |
|---|---|
| Toast for 30 | 6 |
| Toast for 60 | 12 |
| Toast for 120 | 24 |
| Brunch for 20 (mimosas) | 7 |
| Prosecco-led party, 30 guests × 3 glasses | 18 |
For a count tailored to your exact numbers, the wine & prosecco calculator has a toast mode.