There are a lot of benefits to having open credit accounts and using them wisely. Most cards have no annual fee, none will ever charge you anything if you just pay off monthly, and most have some kind of financial reward. This is an entirely separate issue from whether or not you carry debt.
My husband and I have no debt whatsoever and our credit scores are over 800.
But what's your history like? Most people with high scores have low debt but at least a few open, long-standing, well-managed accounts.
Are there different credit score metrics or something? Here in Canada having a credit score in the 700s and higher is considered excellent. At least as far as I know?
I have a score of 750. I pay off all my credit cards/bills on time, and my only debt is a mortgage which is also never paid late.
Yes, there are different scales. The traditional one is 850 points, though there are different ways of calculating the score depending on which software they are using.
For the general population a score in the 700s on an 850 scale is considered excellent.
At MMM and other personal finance sites, the bar is a bit higher, more like 800 out of 850. It's a game you can optimize.
For fun, I did max out at 850/850, based on Discover's reporting. Since the beginning of summer, I have opened 3 new cards and had at least 1 "hard pull" on my credit report. Depending on where you check (Discover, Credit Karma) I'm 829-835 right now.
...but I have a long and rich credit history (multiple cards over 20 years old) 100% on-time payments, don't keep balances on cards, have a mortgage, still have the (paid off) auto loan listed, have earlier (paid off) mortgages listed, et cetera.