How do I get my coworker to stop helping himself to my coffee (that I make daily in my coffee maker)?

Tactfully, no. Since you originally set the ground rule, “I told him in the beginning if he wants to have some, to help himself,” you are going to have to get creative (and possibly give yourself an ulcer).

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Don’t make coffee tomorrow (bring a secret thermos from home) and wander into his office to take a cup from his coffee maker. (Then if it is rotgut, secretly throw it down the toilet).

Next time he heads out, ask him to bring you back a version of coffee that you cannot brew…double, half-caff. mocha, latte, foam art stuff.

It’s an exhausting proposition, I admit.

When he asks for a snack, say that you’re out and it is his turn.

Ask your office mates to help out.

Or think of a zinger, such as, “Hey, neighbor, when is it your turn?”

Ugh.

Coffee is a sacred office product.

This guy is clearly breaking every major coffee rule:

1. Coffee is provided equally by all Coffee Drinkers.
2. He who Takes the Last Cup must Make a New Pot.
3. DON’T TOUCH MY COFFEE.

This guy is a coffee vampire. You invited him in once, and now he’s taking advantage.

How do you kill a vampire? Stake through the heart.

Next time he walks in, let him know what he owes you for restocking your stash, and remind him that this is not the office kitchen, which he can find down the hall and to the right, and if he’d like community swill, he can find it there.

You gave him an open invitation. I agree with @gailcalled. Stop having it available for a while because “you can’t afford it.” Maybe you can then make it a “cooperative effort.” Would the office go for a coffee for all system? Many offices do.

I agree with @Seek_Kolinahr And make sure it is done in a semi-public manner.

Or be devious and put a TABLESPOON OF SALT in the last cup, ask him if it tastes different !

Ask him to chip in if he is going to have some every day.

Last thought; if he continues to take the last cup (really, really rude) that gives you the chance to ask him briefly, clearly and politely to throw out the grounds, wash the pot and brew a new pot. You do have the right to expect the last cup to be waiting for you.

Or, just hire a hit man. We’ll chip in.

Put a jar/can/container next to the coffee pot with a sign that reads: If you take a cup please leave an appropriate monetary contribution. Coffee isn’t free. This means you.

Get a bag or can of coffee, take out the coffee, and replace it with chewing tobacco. That’ll send a nice message.

I agree with not making any for a while because you “can’t afford it.” Could you bring some from home in a thermos or something that you can hide somewhere so you can still have your daily coffee fix?

I hate confrontation too.

@Dutchess III: Today I was going to hide it since he was out, and then I thought that he would not take the last cup. I should have been more on top of things and said what others have suggested, that if he takes the last cup he has to make a new pot. I don’t usually think in “confrontation” mode, but I guess if I am going to deal with this, I’m going to have to.

It can be said nicely (“Hey Mooch. Would you mind making another pot of coffee? Thanks.”) but I would still feel uncomfortable because I know I’m pissed! That’s just me, though.

I know what the problem is! You are expected to be obedient!

If he has a coffee maker in his office, I go in his office in the morning and say, “Hey, I hope you don’t mind if I use your some of your coffee to make us a pot this morning. It’ll be ready in a few. Thanks.”

Try not to think of it as a confrontation. You did offer him coffee, and didn’t put any limits on that offer – so he’s really just doing what you’ve told him to do. But there’s no rule against changing your mind about what you can offer, or how you want to arrange this between the two of you. Just say you’ve been noticing that the coffee costs are starting to add up to more than you expected, and you wonder if he might be willing to chip in to a coffee fund, and make a new pot when he finishes the last. It’s totally reasonable for you to ask that… and it has the added benefit of being the truth.

Place a note on the coffee maker.
One cup free all others will cost you.
If you drink the last cup make a fresh pot.
(But I bet that he’d leave some in it just Not to make a fresh pot).
I suspect that he is using your coffee just to bump into you and talk?
Especially since he has his own pot of coffee?

Taste his coffee before you ask him to make another pot when he empties yours. There may be a reason he doesn’t make his own.

Make enough for you to have one cup. If you want another, make another, don’t leave any in the pot.

They make one cup coffee makers. But that would be a pain, I think.

@Dutchess_III not really, particularly if you go with one of the ones that take the individual serving containers and as a benefit, they come in a variety of flavors. You can change from cup to cup.
But, I think it will be a lot more effective if you made 12½ oz and left only ½ oz in the pot, not enough to make it worth his while and you get the added benefit of saying how sorry you are for not having any left.

There is no “nice” way to do this.

Unhappily, people with this kind of out-exchange are impervious to subtlety and hints that “maybe it’s your turn”.

Fortunately, you can hit them over the head with a bat and no one will usually mind.

Unfortunately, you will feel bad.

Fortunately, your co-workers will cheer for you.

Unfortunately, you’ll still be facing murder charges.

I’d suggest salting the pot (don’t put salted water through your coffee maker!) and carrying an external supply for a few days. When he gags – and blames you for the bad coffee – just tell him you’re trying to cut down, and you find this helps.

You created your own problem when you originally told him to help himself, and obviously he’s not sharp enough to pick up on your annoyance over his taking advantage. Some have suggested a “creative” approach, but I suggest a grownup direct one. As nicely as you can, just tell him (or, if you don’t want to do that, write him) you’d like him to start making his own coffee.

If this pisses him off, it’s his problem, not yours.

I would start by politely reminding him that this is your personal coffee maker and you use your own personally-provided coffee. And then (if you’re comfortable with it) ask him to either bring some coffee in to brew, or to contribute toward the cost of what you bring in. If that does not work, I would then resort to the more severe or extreme methods outlined.

If food-grubbing is his only fault, and he is a good co-worker otherwise, you might consider picking up a cheap coffemaker, maybe at a thrift shop, as a gift-with-a-subtle-message.

I’d be straight-up and just say hey, with the cost of coffee getting so high, I’m going to have to ask that you chip in. Communication can be uncomfortable but it’s important, he probably has no clue he’s being a major mooch.

Or just tell him. “Oi, I know I said help yourself but you helped yourself once too often buddy. So, either bring in some coffee to share or your caffeine addiction is in for some cold turkey!”

Maybe you could put a money jar next to the coffee pot, for “donations.”

There’s a reason this site is funny. Passive aggressive notes are one of the worst things about working in offices with other people. It’s so much better just to talk to the person directly.

Rubber mallet.

Make a bad cup of coffee… a little hot chili pepper once or twice. It worked for me when people were mooching off me. I ordered hot wings just for myself… It worked like a charm.

@talljasperman I probably would be in your office every day if you brought in hot wings and chili peppers. But I’d share my habanero mango salsa and chips.

I agree with @Pachyderm_In_The_Room. All the covert punitive and diversionary tactics are fun to think up, but I don’t see a solution in them. It’s time to tell him that you’re through providing a bottomless well of free coffee. Don’t do anything to sustain your role as coffee supplier, not even accepting donations. Break the pattern.

To soften it, you might ask him if he’d like you to show him how to make his own coffee as good as yours. Then tell him he’s on his own now. Your shop is closed.