Thank you very much for reading my blogs! This motivates me to keep looking for more topics that may be useful to you, for the organization of your event.
My best advice would be to remember that it's always better to make sure that there's no excess of alcohol, to go for responsible intake. The fewer people get drunk at your event, the more it'll be enjoyed by everyone and you'll all avoid awkward moments.
Now, it is also necessary to do the math of how much alcohol you should buy so that you have enough, but also so there's not too much leftover. This is one of the big expenses that you will have to pay for the wedding.
I suggest that you offer long drinks (mixed, not straight). The average of long drinks per person in a 5-hour event is 5 drinks, that is, about one drink per hour. If your wedding takes place at a very warm place, such as the beach, the average drinks intake may be higher, around 1.5 drinks per hour.
Most bottles are 750 ml (around 25 oz) and a drink of distillate should normally be made with 2 oz. of alcohol for it to taste good, which translates to an average of 13 drinks per bottle. If your distillate bottles are 950 ml, then that would mean you'd have 16 drinks per bottle.
In the case of table wines, you can serve 7 glasses per bottle.
If you want to consider serving a digestif, that's also 2 oz. per person, so you need a 750 ml bottle for every 13 guests.
If you decide to include beers, think of 2 beers per person. Many won't drink beer but those who will, might drink it during the whole event so, on average, that would be the number.
Personally, based on the experience I have organized events at Quinta Sauza, most of our national weddings are from people who come from the north of Mexico, and their consumption of beer is higher because that's what they drink the most. On the other hand, if they are foreigners, beer consumption decreases and tequila consumption increases. This is why I recommend that you also consider the preferences of your guests so you know which kind of alcohol they'll drink the most.
I hope you found this information helpful.
I will soon bring more tips for you, keep reading my blog posts!