Plan on 1 drink per person per hour as your baseline — then adjust for your crowd.
For a full bar, budget roughly 50% beer, 35% wine, 15% spirits by drink count.
Champagne toasts need 1 bottle per 5 guests — buy a case extra for refills.
Event type matters: brunches, bridal showers, and weddings skew heavily toward wine and prosecco.
A licensed mobile bar service like Stiir takes the guesswork out of quantities — and handles the serving.
In this guide
One of the most common questions I get from clients across New Jersey is some version of: "How much alcohol should I actually buy?"
It's the right question to be asking — and it's one I've answered for hundreds of events at this point, from 20-person backyard birthday parties in Montclair to 200-guest weddings in Bergen County. Buy too little and you're making a liquor store run at 9pm. Buy too much and you're carrying cases of leftover wine to your car at midnight.
This guide covers everything: the baseline rule, estimates by guest count, how event type changes the math, beer and wine breakdowns, champagne toast calculations, and the case for letting a licensed mobile bar service handle the whole thing for you.
Section 1: The 1-Drink-Per-Hour Rule
Every alcohol calculation starts here: plan on 1 drink per person per hour. For a 4-hour party, that's 4 drinks per guest. For a 3-hour bridal shower, that's 3 drinks per guest.
This is a conservative-but-realistic estimate for a mixed NJ crowd. Some guests will drink less (your designated drivers, pregnant friends, non-drinkers) and a few will drink more, but they tend to cancel out.
From there, adjust based on:
Time of day. Evening events run hotter than afternoon ones. A 7pm party will have a higher per-hour drink rate than a 2pm brunch.
Season. Summer outdoor events in NJ — especially backyard parties — tend to go through more beer and lighter drinks than winter indoor events.
Your crowd. Be honest with yourself. A group of college friends turns a 4-hour party into a 6-drink-per-person event. A corporate cocktail hour with clients is closer to 2.
Whether you're serving food. Heavy food service slows drinking. A party with passed appetizers and a full dinner will run 20–30% lower volume than a cocktail-only event.
Section 2: Alcohol Estimates by Guest Count
Use these estimates as your starting point for a 4-hour full-bar event with a standard NJ crowd. For events shorter than 4 hours, reduce proportionally. For a heavier drinking crowd or a hot summer outdoor party, increase by 20%.
Guests
Beer (cans/bottles)
Wine (750ml bottles)
Spirits (750ml bottles)
Total Drinks
25
30
8
2
~100
50
55
15
4
~200
75
80
22
6
~300
100
110
28
8
~400
150
165
42
12
~600
200
220
56
16
~800
Assumes 4-hour event, ~50% beer / 35% wine / 15% spirits split, 1 drink per person per hour. Add 10–15% buffer stock.
Section 3: How to Adjust by Event Type
The table above assumes a generic "party" mix. Real events in NJ rarely follow that average. Here's how to adjust the split by event type:
Weddings
Wedding receptions typically run 4–5 hours and skew toward wine and cocktails. Plan for 30–40% beer, 45–50% wine, 15–20% spirits. Don't forget the champagne toast — budgeted separately in Section 5.
Bridal & Baby Showers
These events are often 3–4 hours, daytime or early afternoon, and heavily wine-forward. Use 15% beer, 70% wine/prosecco, 15% spirits. Or skip beer entirely if your guest list trends that way.
Birthday Parties
Varies wildly by age group. A 30th birthday party with a mixed group might run 50% beer / 30% wine / 20% spirits. A 50th birthday dinner party will skew much more toward wine. Adjust based on who's actually coming.
Backyard Summer Parties
These run hot — literally. Summer heat accelerates drinking pace, especially for beer and lighter cocktails. Increase total volume by 25% from the table above and skew toward beer: 60% beer, 25% wine, 15% spirits.
Corporate Events & Happy Hours
Corporate events in NJ trend toward moderation. Plan 2–2.5 drinks per guest for a 2-hour happy hour. Split more evenly: 35% beer, 40% wine, 25% spirits (cocktails). Always include a solid mocktail option.
Holiday Parties
Winter holiday parties tend to lean toward wine and spirits. Skip or cut the beer back to 20% and put that volume into wine and a signature cocktail.
Section 4: Beer & Wine Breakdown
Once you know your total drink count and split, here's how to break it down into units:
Beer
1 beer = 1 drink. Simple. For a party, plan a mix of 2–3 styles: a light lager (your highest volume), an IPA or craft option, and optionally a hard seltzer for variety. If you're buying cases (24 cans), divide your beer total by 24 to get case count.
For 50 guests at a 4-hour party needing ~55 beers: buy 2 cases of lager + 1 case of IPA/seltzer = 72 total. Small buffer, no problem.
Wine
A standard 750ml bottle of wine pours approximately 5 glasses. A 1.5L magnum pours about 10 glasses. For a wine-heavy event like a bridal shower, you can reduce per-bottle cost by buying magnums.
Split your wine between red and white, roughly 40% red / 60% white for most NJ event types. Outdoor summer parties can go 70% white and rosé. Add prosecco or sparkling wine for bridal events.
Spirits & Mixers
A 750ml bottle of spirits pours approximately 17 standard 1.5oz shots/cocktails. A 1.75L handle pours about 39. If you're making batch cocktails (which I strongly recommend), 1 bottle of spirits typically goes into a batch that serves 15–20 people.
Don't forget mixers: soda water, tonic, juices, simple syrup, garnishes. Budget roughly 1 liter of mixer per 4–5 spirit drinks.
"The most common mistake I see NJ hosts make? Buying too much of one thing and running out of another. The mix matters as much as the quantity."
Section 5: Champagne Toast Calculator
A champagne toast is calculated separately from your bar supply — it's typically poured right before the toast, one glass per guest. Here's how many bottles you need:
Guests
750ml Bottles (1 glass each)
750ml Bottles (generous pour)
Magnums (1.5L) Option
25
5
7
3–4
50
10
13
5–7
75
15
19
8–10
100
20
25
10–13
150
30
38
15–19
200
40
50
20–25
Standard = 5 glasses per 750ml bottle. Generous = 4 glasses per bottle. Magnums (1.5L) pour ~10 glasses and look elegant on the table.
Pro tip: if your wedding or event has a prosecco or sparkling wine station at cocktail hour, guests will arrive at the toast with glasses already in hand. You can often reduce toast bottles by 15–20% in this scenario since not every guest will reach for a second pour.
Section 6: Planning for Spirits & Cocktails
If you're planning to serve cocktails — beyond just beer and wine — here's how to plan your spirits inventory:
Pick 2–3 base spirits, not 6. A well-curated bar with vodka, tequila, and rum (or whiskey) will satisfy 95% of guests. Spreading your budget across 8 spirits means you run out of everything.
Plan a signature cocktail. One or two custom cocktails with batch-prep dramatically reduces per-drink cost and speeds up service. A pre-batched sangria or punch can serve 20 guests from one batch.
Don't forget zero-proof options. Especially at NJ weddings and family events, mocktails are increasingly expected. A well-made mocktail with fresh juice and soda isn't an afterthought — it's part of the menu.
Buy handles (1.75L) for high-volume spirits. If vodka is your crowd's go-to, buy handles rather than 750ml bottles. You save money and make fewer bottle swaps during service.
Section 7: Common Mistakes NJ Hosts Make
Not accounting for cocktail hour. If your event has a cocktail hour before dinner, guests will drink at their fastest pace during that window. Plan an extra 0.5–1 drink per person for the cocktail hour alone.
Forgetting ice. Plan on 1–1.5 pounds of ice per guest for a summer event. More if you're using an ice bath for beer and wine. Running out of ice at 8pm is a real problem.
Underestimating the bar setup time. If you're doing a DIY bar, allow 45–60 minutes for setup before guests arrive. An experienced bartender can set up faster, but don't plan for guests to walk in while bottles are still being unpacked.
No buffer stock. Always buy 10–15% more than your estimate. Most NJ liquor stores allow returns on unopened, unrefrigerated bottles. Buy extra, return what you don't use.
Buying everything at the last minute. For a party over 50 guests, shop 2–3 days ahead. You don't want to be driving between liquor stores on the morning of your event because your first choice was sold out.
Section 8: Why a Licensed Bartender Changes the Math
Hiring a licensed mobile bartending service like Stiir for your NJ event doesn't just mean someone's pouring drinks while you enjoy your party. It changes the alcohol equation entirely.
We help you plan the right quantities.
Based on your guest list, event length, and type of event, I'll give you a specific shopping list — not a spreadsheet, a list. What to buy, how much, and where to get it in NJ at a good price.
We control pour sizes.
An experienced bartender pours consistently — 1.5oz per cocktail, every time. DIY bars typically pour 2–2.5oz per drink. That's 25–40% more alcohol used per cocktail, which explains why DIY bars run dry faster.
We catch problems before they become problems.
Running low on vodka at 9pm? We see it coming at 8:15 and adjust — shift guests toward the rum punch, suggest opening the backup bottle early, adjust pours. This doesn't happen when a friend is behind the bar.
We handle setup and breakdown.
Everything arrives with us, gets set up before guests arrive, and breaks down cleanly after. You're not moving coolers at midnight.
Ready to stop guessing?
Tell Lexi about your NJ event — guest count, event type, date, and location — and she'll send back a custom bar plan with exact quantities and a quote.
Section 9: Frequently Asked Questions
L
Lexi
Founder & Lead Bartender, Stiir Mobile Bar — NJ & NYC
Lexi has 15+ years of experience in hospitality, event production, and bartending across New Jersey and New York. Stiir serves weddings, private parties, and corporate events throughout the tri-state area.