In general, an unpaid break becomes a paid break in the event that an employer requires an employee to work through the break, or the employer puts some kind of restriction on the break (such as not permitting employees to leave the property). In most cases, a "work emergency" can override an employee's right to a paid break. What follows below is an abridged summary of each province's rules for breaks during a shift.
Alberta
During each shift in excess of 5 hours of work, an employee is entitled to 30 minutes of rest, paid or unpaid at the employer's discretion. This break can be one 30 minute period, two 15-minute periods, or 3 10-minute periods.
Ontario
An employee may not work more than five hours without a 30 minute break, although the employee and the employer may agree to splitting the break into two breaks within that 5 hour period. If the employee is required to be available for work or to work at all during the break it is a paid break.
Newfoundland and Labrador
During each shift in excess of 5 hours of work, an employee is entitled to 60 minutes of rest, paid or unpaid at the employer's discretion. This break must be taken at once and if the employee is required to be available for work or to work at all during the break it is a paid break.
Nova Scotia
During each shift in excess of 5 hours of work, an employee is entitled to 30 minutes of rest, paid or unpaid at the employer's discretion. This break must be taken at once and if the employee is required to be available for work or to work at all during the break it is a paid break.
Northwest Territories
Employees are entitled to one 15-minute paid rest period in every four or three and one-half hours worked as appropriate. Scheduling is subject to the supervisor's approval.
Everywhere Else (BC, SK, MB, QC, NB, PEI, YT, NU)
During each shift in excess of 5 hours of work, an employee is entitled to 30 minutes of rest, paid or unpaid at the employer's discretion. This break must be taken at once and if the employee is required to be available for work or to work at all during the break it is a paid break. "Coffee breaks" or breaks of less than 30 minutes cannot be added up and substituted for a meal break.
Note:
In some circumstances, an employer may apply to their local labour relations board to waive the break requirement in the event that such a break would be incredibly impractical (such as where the site only has a single employee).