How many suits do you really NEED vs. OWN?

I think you only "need" a charcoal suit, since it is appropriate for everything. Although I think that you are better served with three, a black one, a navy one, and a charcoal one.

Six suits for someone who wears a suit everyday is certainly not too many suits. I would think a minimum of about twenty would be about right...each one gets worn once per month and should last many years assuming they are of high quality.

When I wore suits everyday in the eighties and nineties I had about forty or fifty suits, about half of which would fit at any given time depending on my weight.

Keep buying four or five per year and eventually your collection will be pretty large and versatile.

That was from my perspective, of someone that only wears suits maybe 10 times a year.

It depends upon your work and social requirements and your climate. It also depends upon if you enjoy having a lot of clothes or if you enjoy having a well edited wardrobe. If you have the resources it is easy to buy a lot. Some of the best dressed men that I admire don't actually own a lot of suits or clothing. They know what looks best on them and they stick with it. They have a well edited personal style. You can own a lot of suits, ties, sock, shoes, etc and never look that great. Go for what looks best on you and then have enough to rotate your apparel.

I don't need any suits. I wear them because I like them, but I can't afford to be completely frivolous so I have to buy occasionally and carefully. At present I have 5, none of which are conventional business suits - I tend towards texture, cord, tweed, linen. I do give in to pure desire sometimes, as with the Paul Smith golden-brown cord number...

I have one suit. I last wore it about 5 years ago. So I guess I don't need any suits.

I need one or two...

I own aroud 20 of them...

Six suits does seem a bit light if you wear them everyday. Another factor is seasonality and whether or not you want to add flannels for the winter and lighter weights for the summer which can increase the wardrobe substantially.

If you only wear a suit for occasional weddings and funerals, than one is enough. If you wear a suit to work every day, then at least three -- navy, charcoal and pattern (pinstripe, windowpane, etc.). If you wear a suit every day and live in a climate which has hot summers and cold winters, than double that to six. A navy blazer and a few pair of trousers offers a nice change of pace as well. I have about 15 suits -- several very nice summer and winter suits for local wear. I travel a lot to Europe and Asia and have several "travel suits" -- less expensive but still nicely tailored. A 24 hour flight packed in a suitcase to HK can crumple high end suiting fabric.

Take into account how often you wear them versus what your business environment is....

I wear one every day, in a very liberal environment (meaning I can wear funky etro/paul smith patterns) I have maybe 20 suits and another 15 sport coats/blazers.

When I hear someone who wears a suit every day owning less than 10, I have to think that getting dressed might be a challenge and boredom.
- How many are the dry cleaner at one time?
- If you buy 2/3 a year and your weight fluctuates a little, how many still fit you perfectly?

Maybe the exception to the rule is if you have a strict dress code that only say medium grey or navy suits are acceptable. In which case I imagine getting any joy out of shopping for clothes is hard to do.

Certainly there is a lot less wear and tear if you have a deeper closet, and provided you maintain your size, they will last a lot longer than every day wearings.

I own 10 suits, and wear them 2-3 times a week: 1 tan for the summer,5 grey and 4 navy. 2 of the grey ones are winter weight. One of the blue ones is double-breasted for very formal occasions. I don't own any black suits, but should get one for hip occasions. Invest in quality, and if you maintain your weight, with proper care they'll last until the time you don't need to wear any suits at all

I probably need 3 suits (1 navy, 1 charcoal, 1 grey - all solid). However, of the 6 suits I own, only 1 of these is one of the 3 'needed' suits (a solid charcoal). The rest of them are either thin pinstripe or windowpane. That said, one of the windowpanes is so subtle that in many lights, it looks solid. So, I have 6 suits and still need 2 more, despite the fact 3 suits is all need.