Tipping movers is not mandatory, but it's the norm in the industry for good reason — moving is physically demanding work, and a tip is the clearest way to acknowledge a job well done. Here's the straight answer on how much.
For a long distance move that spans 2 days (pickup day and delivery day), tip on each day — the pickup crew and delivery crew may be different people.
Tip at the end of each phase — once pickup is complete and the truck is loaded, tip the loading crew. Once delivery is complete and everything is in your new home, tip the delivery crew. Don't wait until after you've inspected every box — that can take days. Tip for the work that was done.
Cash per person is the most direct and appreciated form. If you tip one person and ask them to "share with the crew," that doesn't always happen. Individual envelopes with each person's name (if you learned their names) is a nice touch for exceptional service.
No. Tips are never included in a moving quote and should never be suggested or implied by the moving company. If a company tries to add a "gratuity" to your invoice — refuse it and tip in cash based on the service you received.
If the move was terrible, you are not obligated to tip. A tip is for work done well. It's not automatic.