The first 72 hours are not just about recovery; they are when you lock in the core proof for safety, causation, benefits and liability. For Ontario readers, the priorities are: report correctly, get an objective medical assessment early, preserve original digital evidence, notify your insurer clearly that you may have injury-related claims, and diary the short statutory timelines that begin almost immediately. Much of this framework is globally useful, but the reporting, SABS and notice rules below are Ontario-specific.
| Police/reporting | Medical | Evidence | Witnesses | Insurer | Lawyer |
| 911 if injury/crime; otherwise local CRC/online route | ED/urgent care/GP for red flags and objective findings | Keep original photos, video, dashcam and vehicle data | Get names, mobiles and a one-line account | Notify promptly; ask for accident-benefits forms | Early advice if fault, road-defect or serious-injury issues arise |
Ontario police, insurer and evidence-retention rules make speed matter: some local CCTV is kept for only about 72 hours, and MTO COMPASS footage for about 15 days.
First response
Safety and reporting
If anyone is injured, a criminal act is suspected, or a pedestrian/cyclist is struck, call 911. For non-emergency but reportable collisions, Ontario’s current property-damage reporting threshold is $5,000, and local police may send you to a Collision Reporting Centre or an online portal; Toronto directs parties to a CRC within 24 hours, while York’s online system requires an incident number and submission within 72 hours. Get the incident number, and then order the collision report from the investigating police service or Ontario’s online/mail process.
Evidence that disappears first
Take wide, medium and close photographs of the scene, damage, road markings, weather, airbags and visible injuries. Save the original HEIC/JPG and video files; do not rely on screenshots or compressed chat uploads. Exif metadata and file hashes can help prove time, location and authenticity, while common chat/image transfers can strip or alter that metadata. Also move quickly to preserve external footage: York police say community-camera footage is retained for roughly 72 hours, and Ontario 511 says MTO highway-camera recordings are kept for about 15 days via FOI request. If liability is disputed, tell the insurer in writing not to repair or dispose of the vehicle until any dashcam or event data recorder is preserved.
Medical steps within the first day
Get examined early even if symptoms feel “minor”. Concussion and whiplash symptoms can evolve over time, and Ontario neurotrauma guidance stresses prompt diagnosis, repeat evaluation and urgent escalation for red flags such as worsening headache, vomiting, double vision, neck tenderness, weakness/tingling or drowsiness. For claim strength, the most useful records are usually objective ones: neurological findings, Glasgow Coma Score where relevant, range of motion, work restrictions, pain score and disability scoring. Do not chase scans for their own sake: whiplash guidance recommends X-ray/CT/MRI only when clinical rules or neurological signs justify imaging.
Insurance and legal communications
What to tell your insurer
Notify your insurer promptly and keep the wording factual: where, when, who, what hurts, what care you sought, and that you want accident-benefits forms if you may be injured. Do not speculate about speed or admit fault; Ontario insurers determine fault under the Fault Determination Rules, not roadside impressions. A useful Ontario-specific safeguard is to say explicitly: “I may have injuries and I want to preserve my accident-benefits rights.” If you want a consumer-facing cross-check, Ontario Collision Help is one Ontario resource, but your own contemporaneous records remain the primary evidence.
Deadlines you should diary immediately
Under the SABS, notice of intention to apply for benefits should go to the insurer no later than seven days after entitlement arises, or as soon as practicable, and the signed application is due within 30 days after you receive the forms. Most Ontario tort claims are subject to a basic two-year limitation period from discovery. One non-obvious trap: if a pothole, road defect or municipal maintenance issue may have contributed, special written notice can run in 10 days. Recent Ontario case law has taken a consumer-protective view of notice in Hussein v Intact, but treat that as a safety net, not a plan.
A five-minute documentation template
Create a single timestamped note today with: date, time and exact location; lane/direction and weather; who said what; witness names and numbers; symptoms by body part; every treatment visit; every insurer or police contact; and every expense. Email the note and original files to yourself in a form that preserves metadata. That simple “day-one memo” is often more persuasive than a polished reconstruction written weeks later.