Pastrnak signed a 6-year, $40 million contract ($6.6M AAV) with the Bruins on September 14th, 2017, which expires at the end of the upcoming 2022-23 NHL season.
As a comparable, Kevin Fiala recently signed a seven-year, $7.785 million contract with the Los Angeles Kings, but Pasta's next contract is reported to be well north of that amount.