Most experts agree that between 5% and 20% is the perfect range. Most moving companies allow customers to tip cash. Every move is different and, as such, there are many factors at play when deciding how much to tip those who move. If you're moving across the street with a 2-person team that only takes a few hours, the tip amount must be less than someone moving a five-bedroom house across the country.
The general rule of thumb is to base the tip on a percentage of the total cost of moving, with 15-20% being the industry average.