Ontario · Ontario Parks · Car camping
When can I book Ontario Parks? Count the five months from your arrival.
Ontario Parks says you can reserve a campsite at most parks five months before your date of arrival. Enter the date you want to arrive and see the day your booking opens, with the month-end case flagged.
Short answer: Ontario Parks says you can reserve a campsite at most parks five months in advance of your date of arrival. For a Saturday, July 17, 2027 arrival, that is February 17, 2027, a Wednesday. If the arrival day does not exist five months earlier, such as a 31st, the calculator uses the last day of that month and flags it as unconfirmed.
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Result
Enter your arrival date and press Find the booking date.
What Ontario Parks says
On its car camping page Ontario Parks states: you can reserve a campsite at most parks five months in advance of your date of arrival, and reservations can be made online or through the call centre at 1-888-ONT-PARK. The same page notes that some of the most popular parks, naming Killbear, Sandbanks and Pinery, fill up quickly while many others have sites available. The reservations page gives the call centre’s hours as 7 a.m. to 9 p.m. Eastern Time, 363 days a year, closed on Christmas Day and New Year’s Day. That 7 a.m. figure is the phone line’s opening hour; the pages I read do not say when the online booking window opens each morning, so this calculator gives you a date and not a time.
Two details are left open by that sentence. It says “most parks,” and the pages I read do not list the exceptions, so check your park. And it does not say how five months works at the end of a month: counting back five months from a July 31 arrival lands on a February 31 that does not exist. The calculator then uses the last day of that month, February 28 in 2027, and marks the result as unconfirmed so you can check it with Ontario Parks. It never rounds to the first of the next month.
Read the Ontario Parks car camping page ↗ Ontario Parks reservations ↗
Worked example: a July 2027 weekend
Say you want to arrive on Saturday, July 17, 2027. Five calendar months earlier is February 17, 2027, which is a Wednesday, so that is the day the window reaches your arrival date. Counting from October 26, 2026, the day this page was written, that is 114 days away. If instead you plan to arrive on Saturday, July 31, 2027, the count lands on February 31, so the calculator shows Sunday, February 28, 2027 and flags it. The difference matters: someone who counts to March 1 would book a day late.
The reverse question has an answer too. Today, October 26, 2026, the latest arrival date inside the five-month window is March 26, 2027, a Friday. Each day that passes moves that latest bookable arrival forward by one day, which is why the tool also shows it for the day you open the page. For a popular park on a summer weekend, the sentence from Ontario Parks about fast-filling parks is the reason to be ready on the opening day.
Method
The tool subtracts five calendar months from your arrival date, keeping the day of the month. When that day does not exist in the earlier month, it uses the last day of that month and says so. The number of days until the window opens is the difference between that date and today’s date in your browser. The latest bookable arrival is today plus five calendar months, handled the same way. All dates are calendar dates with no time zone or time of day, and nothing you enter is sent to our servers.
What this does not cover
- Parks that do not follow the five-month rule. The source says “most parks” and does not name the exceptions.
- What time of day the window opens online, which the pages I read do not state.
- Availability, fees, minimum stays or reservation penalties, which are on the Ontario Parks pages.
- Backcountry, group or roofed accommodation, which the car camping page does not cover.
- A promise that the date is correct for your park. Confirm on the reservation site before you plan around it.
Sources
- Ontario Parks, Car camping (reserving a campsite five months in advance) (retrieved October 2026)
- Ontario Parks, Reservations (call centre hours) (retrieved October 2026)
Common mix-ups
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Often assumedOntario Parks opens all of a summer's campsite reservations on one day each year.
What the source saysOntario Parks says you can reserve a campsite at most parks five months in advance of your date of arrival, so the window moves with the arrival date rather than opening on one fixed day. The page says most parks, without listing exceptions. [1]
Checked against these sources on .
Frequently asked questions
How far in advance can I book Ontario Parks?
Ontario Parks says you can reserve a campsite at most parks five months in advance of your date of arrival, online or through the call centre.
What time do Ontario Parks reservations open?
The pages I read do not give an online opening time. The call centre’s hours are 7 a.m. to 9 p.m. Eastern Time, 363 days a year. Check the reservation site for the online release.
Is the five months counted by the arrival date or the last night?
Ontario Parks says five months in advance of your date of arrival, so the count starts at the day you arrive, not the day you leave.
What happens if my arrival is on the 31st?
Five months before a 31st can land on a month with no 31st. The pages I read do not say how Ontario Parks treats that. The calculator shows the last day of that month and flags it as unconfirmed.
Do all Ontario parks use the five-month window?
The source says most parks. It does not list the exceptions, so confirm the rule for your park with Ontario Parks.
Which Ontario parks fill up fastest?
The Ontario Parks car camping page names Killbear, Sandbanks and Pinery as popular parks that fill up quickly, while many other parks have sites available.
Can I book by phone?
Yes. Ontario Parks lists a call centre at 1-888-ONT-PARK, open 7 a.m. to 9 p.m. Eastern Time, 363 days a year, closed on Christmas Day and New Year’s Day.
Unofficial tool: not run by Ontario Parks
This page is not operated by Ontario Parks or the Government of Ontario. It applies the five-month rule stated on the Ontario Parks website as a date calculation; the operator’s own system decides what you can actually book and when. Confirm on the official reservation site. General information only.