A passport book is an accepted form for any type of travel between the two countries, but can also be used if a flight may be necessary for traveling. If there is any chance of flying when visiting Canada or if there is a possibility of taking a flight to another country in the future, it may be best to get the passport book for travel to and from Canada. The book will cover all means of travel in the future.
If there will be no need to travel via airplane a passport card with work for admission across the border between the United States and Canada. The passport card is only the size of a driver's license, making it easier to carry and travel with. The card will work for any land or sea travel across the border, but is not accepted for air travel.
The enhanced driver's license is one that is issued only by a few states which border Canada and for those who frequently travel back and forth between the two countries. The license denotes the person's identity and citizenship, similar to the passport card without all of the passport applications. The enhanced driver's license is currently being issued in New York, Michigan, Vermont and Washington.
