$0 - $40,726 (with $10,320 basic personal tax credit): 15%
$40,727 - $81,452: 22%
$81,453 - $126,264: 26%
Over $126,264: 29%
As can be seen above, Canada has only four tax rates. The US, however, has six.
Why hasn't anybody proposed adding tax brackets? On a relevant note, here's a potential threshold for a new tax bracket:
"The first $400,000 (for 2008, federally) of active business income of a Canadian controlled private corporation, or CCPC, is taxed at lower rates. The tax reduction is called the small business deduction."
Another threshold was suggested by Oskar Lafontaine of Germany's Left Party (Die Linke): above 600,000 euros. In Canadian dollars, that would be about $1 million.