Here are two sentences:
1: “At Nemo’s Aquarium, we are committed to making sure you are happy with your new fish.”
2: “At Nemo’s Aquarium, we’re committed to making sure you’re happy with your new fish.”
See what I did there? Which do you prefer? (I’m hoping no-one says 1.)
This is not about lowering your word count or using fewer characters; the saving is pretty trivial in any case. What it’s about is talking to your customers, even when what you’re saying is written down.
Most of us are trained to write in a rather formal register, one that we’re taught looks “professional”. The result is, when we’re writing things down, we tend to do things we’d never dream of doing when we’re talking. So we write “I am, you are, she is, cannot, should not, would not” when what we’d usually say is “I’m, you’re, she’s, can’t, shouldn’t, wouldn’t”. I do it myself, constantly, which is why I’ve adopted this handy little technique to make my writing instantly look more friendly and conversational:
Anywhere you’d use a contraction in speech, use it in writing too.
Now, there are certainly some contexts where I wouldn’t do this. If I were a funeral director writing a brochure for customers, then a formal register might be more appropriate. Or there might be a certain tone I want to capture: the other day I was editing some copy for a feng shui consultant, and I ended up leaving some of her non-contractions uncontracted (so to speak), because I felt the slight echo of the stilted tone of ancient Chinese proverbs in translation gave a subtle psychological boost to the credibility of what she was saying.
Then there are situations where you need to spell something out for emphasis, or a contraction just looks awkward (I’m not recommending “would’ve, could’ve, should’ve” or contractions using multisyllabic nouns like “our prices’re the lowest”).
Most of the time, though, using the contraction is better whenever you’re writing something for customers. And yes, that includes business customers. Some of you, I know, already do this reflexively. This advice is for the rest of us, those of us whose writing style has developed over hundreds of school and university assignments and who have a drummed-in fear of anything sounding too casual. To those people I say, try letting some apostrophes into your life. See if you don’t like it.

