I guess I could leave it at that. But clearly, that's too short for a blog post so I'll elaborate.
Confession: 2 1/2 years ago I interviewed for 2 jobs wearing a dress instead of a suit. I didn't get those jobs. Now, I'll never know if there was a relationship between my apparel choice and the rejection that later followed...but shortly after that experience I went out to Banana Republic and bought a new suit. I didn't get the next job I interviewed for, but I did get my dream job a couple months later.
Candidates wear a suit to their interviews with me about 30% of the time. About 60% of the time they wear something along the lines of business casual - black pants, dress shirt, a knit dress. About 10% of the time they wear something borderline casual or obviously stained. When I used to interview temporary employees for a phone job about 10% of the time their cleavage was so abundant that I admit I was completely distracted by it.
Here's the thing...you don't HAVE to wear a suit. But anytime a candidate comes in wearing a suit I immediately think to myself "wow, she puts herself together well...seems professional ...seems respectful...could take her to a meeting with a big corporate sponsor." That's exactly where my brain goes. You see, I only have about an hour to size you up for the first time and by wearing a suit, you are giving me a chance to picture how professionally you could present my organization.
Now, I understand that buying a suit can be an expensive undertaking, especially for a new grad. However, the most important thing is that it fits and you feel relatively comfortable in it. (I say "relatively" because I find most suits pretty constricting and still feel like I'm playing "grown up" when I put one on). There are lots of great deals at places like Macy's and TJ Maxx where you can find suits that will more than suffice. At the very least, invest in a grey jacket and a black jacket that you can mix and match in case you have multiple interviews with the same company.
Remember, wearing a suit can't hurt and sure could help. So, just take the guesswork out and wear one!