TFSA (Canada)
A Tax-Free Savings Account. You contribute money you have already paid tax on. Growth and withdrawals are tax-free.
Unused room carries forward every year, and anything you withdraw is added back to your room the following January.
RRSP (Canada)
A Registered Retirement Savings Plan. Contributions reduce your taxable income today, which often means a tax refund. You pay tax when you withdraw, usually in retirement when your income is lower.
FHSA (Canada)
A First Home Savings Account for first-time buyers. Contributions are tax-deductible like an RRSP, and withdrawals for a qualifying home purchase are tax-free like a TFSA.
401(k) (United States)
A workplace retirement plan. Money goes in before tax, often with an employer match. Contributing at least enough to get the full match is one of the best returns available, because the match is free money.
Many plans also offer a Roth 401(k): you pay tax now, and qualified withdrawals in retirement are tax-free.
IRA and Roth IRA (United States)
Individual Retirement Accounts you open yourself. A traditional IRA may lower your taxes now; a Roth IRA is funded with after-tax money and grows tax-free, with income limits on who can contribute.
Which comes first?
It usually depends on whether your income is higher now or will be higher later. Contribution limits and rules change every year, so check the current numbers from the CRA or the IRS before you contribute.