This is a story about being cunning...
Where I'm currently working, there are very few occasions where it would become apparent that I'm presently teetotal. However, in the financial services districts of London - The Square Mile and Canary Wharf - a teetotaller is automatically suspected of being a recovering alcoholic, which is not a label which anybody wishes to have attached to them, let alone if it's untrue.
One dreadful mistake I made in 2015 was to agree to go to a colleague's birthday party in a cocktail bar, at the top of a skyscraper, with panoramic views over London. It was pretty obvious that alcohol consumption was very much part and parcel of the social engagement, but I agreed to go anyway. Of course, there was a great deal of arm-twisting and attempts to persuade me that "one drink won't hurt", which of course it wouldn't have done, but I pride myself on taking my commitment to challenges seriously, and not taking any short-cuts or cheating. Of course it's totally possible to have a period of so-called abstinence, but break the rules whenever you like, but what have you really achieved? You might as well not have bothered. Anyway, I had a cast-iron excuse, so I managed to swerve having to drink just to prove that I'm not a recovering alcoholic.
The watertight excuse for a period of being teetotal, which I have used before and again now, is to say that I am taking part in the "Go Sober for October" sponsored abstinence from alcohol. Thus, if I face any questions about why I'm not drinking, or pressure to drink, I can easily address that by saying that my sobriety is part of a sponsored charity event.
You might believe that simply saying "no thanks" or "I'm not drinking at the moment" would suffice, but in fact British culture, and especially London banking culture, tends to lend itself towards peer pressure and/or a grilling on your justification for abstinence. I remember one JPMorgan colleague was known throughout the organisation as "that guy who went to The Priory and is a recovering alcoholic" because he didn't drink. As I said before, those kinds of labels and reputation are extremely unhelpful, and indeed detrimental to the impression that your colleagues have of you, such that it might present an [unfair and unjustified] impediment to career progression.
My plan and my strategy is fairly simple: don't have any alcohol in the house, avoid social occasions where drinking is part and parcel of the event and have a cast-iron excuse for being [temporarily] teetotal.
What I noticed in 2015 was how determined people are to get you to drink. I had to fend off an AirBnB host's repeated offers of a drink, despite me making crystal clear that I would not imbibe a single drop of alcohol, because of the aforementioned "Go Sober for October" event. Friends and colleagues went to great lengths to persuade me that I could 'cheat' and it wouldn't matter. I withstood all that arm-twisting, but it wasn't easy, even with my well-laid plans and excellent preparations.
I suppose I'm not the best person to write comprehensively on the topic of being teetotal, because my episodes of abstinence are infrequent. Speak to somebody who's spent any great length of time - years, not days or months - and they will have much better strategies and techniques than I do, for politely declining to drink.
Anyway, it's hard, but it's possible and made easier with some careful preparation.