how exciting! Jake got his first collar as a coming home gift..so I don't remember the size! You can measure to be sure..and remember..it's best to use a harness..but you do want them to get used to a collar and leash. It takes almost two years for their chests to finish growing..so just know you will need more than one harness! Jake has tags on his ollar, evn tho he is chipped. On the ID tags..we put our cell and home numbers...the less info..the bigger the writing is for people to read! Good Luck..can't wit to meet him!