What Color of Suit Should I be Looking For?

These days, you can find a suit in just about any color of the rainbow, from a pure dark black, all the way to a shimmering pink or baby blue, and every color, shade and pattern in between.  This guide is meant to help you start a good collection of suits.  In this guide, I will be assuming that you're using a suit for either a formal or work situation.  While suits and sportcoats exist for casual and informal situations, this is somewhat beyond the scope of this guide.

To help you get started, I'm going to describe in ascending order the number of times you might wear a suit, from the once in a while, to you're wearing a suit 5-6 days a week and want to get a little more variety in your wardrobe.  I will also include an in-depth introduction to the different patterns you might commonly find on a suit.

Let's Get Started!!

You: Wear a suit only occasionally, and own only one

The simplest and most basic, multi-purpose suit colors are Dark Navy Blue, and Charcoal Grey.  A solid (no pattern) Navy Blue or Charcoal suit can be worn for just about any situation, from an interview to a wedding to a funeral to church, to wherever you go.  Solid pattern fabrics are your simplest choices here, but a nice shadow stripe could work as well (please see the section on stripes and patterns below).  Try and find a suit with a blazer that can be worn casually (just try and find a very comfortable one, at least).  A good Navy or Charcoal blazer can help make MANY different outfits, and can even be worn with a collared sportshirt and a good pair of jeans to make a good "night out at the club" outfit.
Now's not the time to skimp:  Since you only own one suit, get the best quality one you can comfortably afford.  Well taken care of, it will last you many years, and will never go out of style
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Note: While a black suit might seem to be an obvious choice here, try to avoid it.  Black can come across as very severe (especially on a larger person), and it can also tend to minimize one's size (not so great if you're a smaller person).  Black is also not suitable for all occasions.  It might be great at a funeral, but not so great if you're attending your friend's wedding!

You: Wear a suit 3-4 days a week, and own two or three

The simplest way to add some distinction in your wardrobe is to consider a pattern in your suit.  A nice pinstripe or rainstripe would look good here, possibly a glenplaid (again, please see the section on patterns below). 

As for new colors for your suits, a fine dark green and/or a light grey suit tend to have multiple uses (though not as many as a Navy or Charcoal suit), and tend to compliment most skin types.  Dark green, light grey, charcoal grey and navy suits are ALL fairly easy colors to find different co-ordinating shirt/tie combinations for, as well.  This can really help to add some variety to your wardrobe.

You: Wear a suit 5-6 days a week, and own 4+

Again, a great way to add some variety to your suit wardrobe is to try and find a suit in a color from the above two lists in some sort of pinstripe or pattern.  You can get a pinstripe suit wear the stripes are a different color from the rest of the fabric (and not just white or black).  While this can make matching a shirt/tie a little more difficult, it can really stand out.

As for the final colors, a good beige or sandy coloured suit and a dark (chocolate) brown suit are really the final frontiers, here.  I've left this range of colors (the "browns") to the last, as matching a brown-toned suit (beige, dark brown, burgundy) to your skin color can be a little difficult.  You might find that a particular tone will wash you out (make you look very pale), while the colors in the first two lists (grey, navy, dark green) generally won't do this.  You could also consider a lighter shade of blue or green, but these tend to be a little less formal or business-like.  All that being said, a light grey or light beige suit is probably the most comfortable color (fabrics aside for a moment) to wear during the summer.  Remember, light colors reflect incoming light!

Colors to Avoid (In professional situations)

White
Cream
Baby Blue
Pink
Yellow
Light Green
Orange
Light brown (this'll make you look like a used car salesman, trust me!)
Red (this is considered a very aggressive colour, not great in professional situations)

Of course, you can essentially throw this list out the window when it comes to informal situations.  Then it becomes more of a personal taste thing.  Remember, though, that this guide is meant to help you pick colors for a business or professional setting, where first impressions and look are extraordinarily important.

Patterns

A pattern is a great way to make a you stand out a little or throw a little bit of variety into your suits.  I'm only going to be talking about patterns you might find on an ENTIRE suit, so I will be leaving out tweed and plaid here.  While these are excellent patterns, and can be very professional, they are very rarely found on an ENTIRE suit.  Instead, they are more likely to be found on just a blazer.

Stripe Patterns

The most commonly found type of pattern on a suit is a vertical stripe of some sort.  There are actually four distinct types of stripes found on suits, and they vary in impact, from low, to very high.  As a rule, you should NEVER buy a horizontal stripe suit, it will make you look shorter and fatter than you are, and who wants that?

As far as stripes go, it is not uncommon to find different types of stripes on a single suit.  A common combination, for example, is a Shadow Stripe (or Tone-On-Tone) paired with a thin pinstripe.  Whether this is good or not is completely a matter of personal taste: if you like it, go for it.

The Shadow Stripe

The lowest impact of the stripes, the shadow stripe is generally only a slight difference in texture or shade, rather than a different altogether color (such as white on black).  A shadow stripe will always be a solid line that goes all the way down the fabric.

This is a shadow stripe suit.  Note how the stripes seem just a little bit different from the other fabric.  This is also called a Tone-On-Tone stripe.

The Rain Stripe

The next level up in impact is the Rain Stripe.  A rain stripe is a straight line of dots that that go down the front of a suit.  It is similar to a pinstripe in that it is a different color from the main fabric, but differs in that it is a line of unconnected dots rather than a single solid line.

A classic white-on-black rain stripe.  Note that the dots are not connected.

The Pinstripe

The pinstripe is the classic stripe of suits, and is generally the first thing that comes to mind.  It is a straight, solid, thin line of a different color than the body of the suit that extends down the length of the suit.  Classically, the pinstripe is white, regardless of the background fabric color, but these days, you can get many different combinations.

A classic white-on-charcoal pinstripe.  Notice that the line is solid down the front of the fabric.

The Chalk Stripe

The Chalk Stripe is the largest and most visible of the stripes.  It does make a somewhat bold statement, and certainly draws attention to itself.  It is similar to a pinstripe in that it is a solid line of color, different from the background color, but a Chalk stripe is considerably thicker.  Generally, anything thicker than 1/8" is considered a Chalkstripe, thinner is a Pinstripe (just a guideline).

A white-on-black chalkstripe.  Note how much more this stripe stands out than the pinstripe above.

Geometric Patterns

As there are different stripe patterns that can be found on suits, there are different geometric patterns that can be found as well.  They vary in impact from the very subtle to the very bold

The Nailhead

The nailhead is the most subtle geometric pattern.  It consists of a solid background color and little "pinheads" (or small nailheads) of fabric spaced at regular (and very small) intervals.  The effect of this pattern is that the background color tends to overshadow the nailhead pattern, but the nailhead pattern can easily be brought to dominance by wearing a tie or shirt of the same color (this make the eyes much more likely to pick up the less obvious color in the suit).  This can be a great suit multi-purpose suit.

A light brown/grey nailhead.  The colors are close enough that when worn as a suit, they can merge together.

The Glenplaid

The glenplaid is a traditional English pattern, and not to be confused with a multi-color plaid.  In this case, there is again a strong base or background color, but instead of little "nailheads", there is a different (or in some cases MANY different) colors of threading running through that creates multiple square patterns on the fabric.  This is generally very subtle, and I'm not kidding when I say there are MANY different threads.  I've seen a fine Ermengildo Zegna suit that had a glenplaid made up of not less than 8 different color threads!

A stone and grey glenplaid color.

The Houndstooth

The houndstooth is the most impacting of the geometric patterns.  Two different colors of thread are generally involved, and there is no "background" color.  Each threading is used equally.  The fabric is woven in a certain design, often similar to a tiny lightning bolt.  When the colors are very different, this pattern really stands out, but it can be made more subtle by using colors that are similar.

A houndstooth.  Notice that neither color is really "dominant" in this case.

Well, that's about it.  I've given you an in-depth primer into the various colors and patterns available and suitable for a professional suit.  Remember, if you're in doubt, Navy Blue!