There are two types of messages you can send in Sales Navigator to engage leads and support your sales efforts: free InMails and InMails that use credits.
Free InMail
When sending a message to a 1st-degree connection, or to a prospect with an Open Profile, the message is sent as a free InMail. Sending a free InMail message doesn’t use an InMail credit. However, it’s calculated as part of your InMail response rate.
Important to know
The Open Profile Premium feature allows members to contact a Premium member for free. However, in an effort to keep LinkedIn safe and professional, we limit the number of Open Profile messages you can send in a given time period.
InMail
When you message someone you're not connected with, it will be sent as an InMail. Sending an InMail message uses an InMail credit and is also calculated as part of your InMail response rate. However, you will receive an InMail credit for every InMail message that receives a response within 90 days of the date sent.