- American residents are fleeing from the presidency of the US business mogul
Access to the site became progressively more difficult during Tuesday evening as the Republican candidate picked up key states essential to winning the White House over Democrat Hillary Clinton.
The site displayed an error message at 11pm Tuesday (0400 GMT Wednesday) when the swing state of Florida went to Trump, a major step toward the 270 electoral votes he needed to succeed President Barack Obama.
The immigration website explains the steps to take and the criteria necessary to be eligible for residency in the country or for Canadian nationality.Americans in recent months had vowed to decamp to Canada, led by the Liberal government of Prime Minister Justin Trudeau, if the US mogul were elected.
Canadian real estate agencies and some regions with sparse populations have used the election to launch marketing campaigns.
Early this year, when Trump was just one candidate among a dozen Republicans, the island of Cape Breton in Nova Scotia on Canada's east coast, offered to welcome Americans who wanted to avoid a Trump presidency.
Under the slogan, "Cape Breton if Donald Trump wins", it said jobs and cheap homes are available in a region "with a population problem" just 250 miles (400 kilometres) from the US border.
Many US celebrities have pledged to move north if Trump prevailed over Clinton, including "Breaking Bad"' actor Bryan Cranston, singers Cher and Barbra Streisand, and Lena Dunham, star of the TV series "Girls".
The Canadian foreign ministry's website was also difficult to access during Tuesday evening.