Getting a mortgage in Ontario takes four kinds of documents: identification, proof of income, proof of your down payment and where it came from, and a summary of what you already owe. Lenders want all four before issuing an approval. Paperwork for the property itself arrives later, once you have an accepted offer.
Identification is the easy part: government-issued photo ID with your current address, plus your social insurance number so the file can be matched to a credit report.
Income is where most applications slow down. Salaried applicants are usually asked for two or three recent pay stubs and a letter of employment dated within the past month, then two years of tax paperwork behind it: T4s, T1 General returns and Notices of Assessment from the Canada Revenue Agency. If you are paid partly by commission or bonus, expect the lender to average the last two years rather than use your best one. Business owners face a longer list, generally three years of filings plus articles of incorporation or a business licence, which is why getting a mortgage while self-employed takes more preparation.
This trips up first-time buyers more than anything. Lenders want 90 days of statements for every account holding the money, because they are required to trace where it came from rather than simply confirm a balance. A large deposit that appeared last week will be questioned, and money from a crypto sale or a line of credit needs its own paper trail. When a relative is helping, the file needs a signed letter confirming the money is a gift with no repayment expected, which is covered in more detail in how a gifted down payment works in Canada.
Credit card balances, car payments, student loans and support obligations all feed the ratios a lender uses, and whatever you state is checked against your credit report. After an offer is accepted, your lender and lawyer work from the agreement of purchase and sale, the listing, the legal description of the property, and confirmation that home insurance starts on closing day. Condominium purchases add the status certificate.
Mortgage brokers and agents in Ontario are licensed by the Financial Services Regulatory Authority of Ontario under the Mortgage Brokerages, Lenders and Administrators Act, 2006, and any of them can tell you what their lenders ask for. Pulling the documents together before you tour homes is what separates a rough estimate from a genuine pre-approval.
Related reading: Pre-Qualified vs Pre-Approved for a Mortgage, How Do You Get a Mortgage If You're Self-Employed in Canada?, and What Does a Mortgage Broker Do in Ontario?