How do I reset my master password using a hint/reminder?

If you previously set up a master password hint/reminder (either during account creation, when you last changed your master password, or by manually entering one into your Account Settings), you can have LastPass send you a clue in a reminder email.

Navigate to https://lastpass.com/forgot.php.
Enter your email address and click Send Hint.
An email is sent to your inbox containing the word(s) you set up as a clue to remind you of your master password.

Tip: If you do not receive an email with a password hint, you may have set up a secondary security email where the email was sent instead (learn more). Additionally, please check your spam/junk email filters.
If your hint helps you remember, try logging in to LastPass once again.

Troubleshooting: If your hint does not jog your memory, click LastPass account recovery within the email and follow these instructions to recover your master password with a Recovery One Time Password.

What to do next: Create new Recovery One Time Passwords on trusted devices (strongly recommended)

Create new Recovery One Time Passwords for account recovery (in case your master password is ever forgotten) by doing the following:

Log out of LastPass on every trusted computer and/or mobile device where you have installed LastPass and accessed your LastPass vault. You can check your active sessions for all devices.
Log back in with your new master password.

What to do next: If you are using a public/untrusted computer (recommended)

Clear the browser cache on all web browsers where you accessed LastPass in order to clear the Recovery One Time Password that was created from accessing the LastPass website.

What to do next: If you use temporary, one-time passwords (optional)

Generate new temporary, one-time passwords because all OTPs you generated previously are now invalidated and no longer listed due to your vault being re-encrypted from your master password change.