My wife and I are having lunch with a couple of friends in Manhattan, and I am planning to bring three half bottles. The restaurant charges us $25 per bottle corkage, and whatever they do is acceptable, but I am curious if they should charge the full amount per bottle.
And of course, that begs questions for large formats as well, what do you charge for magnums, double magnums etc?
I know I get charged double for mags and 4x for DMags, and have no problem with that. So to be symmetrical, I’d think 1/2 price for 1/2 bottles makes sense.
Took a second. Should have called them tenths 
That took me an extra second to see why you were bringing old school measurements into this, then I saw the title of the post. I just did the calculation, fifths used to be 2 ounces more wine per bottle than 750 ml. And we all know what happened to prices not too long after the change to metric.
Mark, I can’t imagine a NY restaurant would charge you $12.50 corkage for a half bottle. It will be a nice surprise if they do.
It’s logical, except that the reasons for corkage aren’t exactly linear to volume. For example, the labor of pulling the cork is the same on a 375, 750, or 1.5 (it might be harder on a double mag with larger cork). On the other hand, the volume served (and glasses needed) for a mag may be larger. Nothing’s going to be perfect, but if its $25 for a 750, I would say $15 for a 375 and $40 for a mag would be more in line.
I often find that restaurants will charge single corkage for magnums, not because I fooled them or anything, but somehow they just do.
I’ve never tried bringing a half bottle to a restaurant - I’m not sure most probably even see that happen and have a policy for it, so my guess would be it’s going to be a judgment call / negotiation. Part of the reason I don’t do it is to avoid the awkwardness of that discussion.
As a matter of logic, the fee is primarily for lost wine sales opportunity and glassware use, so it probably should be 1/2, just as a magnum should be 2X.
This is more a hypothetical and the restaurant is one I do a lot of large scale custom dinners as well as regular lunches (and they have halved the cost of corkage) so believe me, if they do charge normal corkage, it is not an issue. But as I have been charged double for magnums, I thought it an interesting question.
To get technical, a fifth is 757 ml. That’s only l% greater, and variation in fill could make it less.
Peter Hickner
I believe that the corkage should be for number of corks pulled. So, yes, 375ml the same as 750ml. Waitperson/Somm still has to pull the cork and provide a fresh glass, no matter what the size. I am not talking over 1.5L size, here.
Personally, I also figure in how many stems, how many people, how many “gift” stems and pours you request to have provided to those people who are staring at your bottle or you know personally. It is not an equation - it’s a sense of how much benefit you received for having the privilege of taking your own wine into a restaurant.
And this is elementary, but do not forget that the waitperson did not get the cost of a bottle or two or six added into the check. Care, common sense, appreciation, and the desire to be welcomed back to that establishment would be my guiding rules.
I should’ve been more exact in my post. A fifth of a gallon is 25.6 ounces, and 750 ml is 25.3632761 ounces, so the difference between yesterday and today is slightly greater than .2 ounces (edited down from 2 ounces, too much wine at lunch today).
The TTB allows us some leeway in filling bottles slightly more than 750 ml and slightly less, but it’s supposed to average exactly 750 ml, if you add up all the overfills and all the underfills. I haven’t heard of a winery getting busted for over or underfilling on a consistent basis. Their main concern would be that we’d be paying the wrong excise tax, either too much or too little.
I think the corkage for a magnum, 750 or 375 should all be the same. One cork to pull. Same number of glasses.
So $10 to pull a cork and $5 a glass?
It is an interesting question Mark.
I never thought about it. I’ve brought 500ml bottles to restaurants and never got a pro-rated charge.
It’s logical, except that the reasons for corkage aren’t exactly linear to volume. For example, the labor of pulling the cork is the same on a 375, 750, or 1.5
Andrew - more often than not, I’d prefer to open my own wine. The “corkage” fee is mostly for the glasses and sometimes decanters and for the real estate - it’s pretty rare that I’ve been with people who ask the staff to open the wine. And of course, you never want them to pour.
(PS - Mark they often waive the charge if you bring something good. I don’t know but maybe if you avoid some of the plonk . . . 
)
We had a local wine store that sold you the wine and if you wanted to sit at their bar and drink it, they charged you corkage. I was floored. I come into your store/winebar buy your wine and you charge me $15 corkage if I want to drink it there??? I know what it costs to open a bottle and wash glasses but corkage to me was always for restaurants to cover loss of sales, not opening a bottle and washing glasses.
That seems so ludicrous that perhaps it was required by law or regulation?
If a coupe gets charged half as much as a sedan going through the Holland Tunnel you may have an argument.
but is tunnel toll not figured by the axle?
Try going through on a unicycle. Please report back! 
was told that self-propelled conveyances are not permitted in the Holland.
sorry.
Corkage is not for labor. It is for lost profit (markup) on not selling a bottle from stock. So corkage on a tenth should be somewhat less.
Phil Jones