\r\n\r\nJustin\u00a0and\u00a0Hailey Bieber\u00a0are thiiiiiissss close to finally pulling the trigger on a date for their formal wedding celebration ... we've learned it looks like the party will go down next month.Sources close to the couple tell TMZ ... they're eyeing a date in September for close friends and family to help celebrate their marriage. The timing shouldn't come as much of a shock, since they got hitched last Sept. 13 at an NYC courthouse.The shindig could serve as both an anniversary and wedding party.\r\nTMZ.com\r\nOur sources say the exact day hasn't been set ... but JB and HB plan to send out invites in a week.As for\u00a0married life\u00a0... we're told Justin is in a great space both personally and creatively and couldn't be happier. Friends say he and Hailey are a perfect fit.\r\n\r\ninstagram.com\/p\/B1M9HcNnZ7a\r\n\r\nJustin posted a love letter to Hailey Thursday, saying, "I fall more in love with you every single day. You are the greatest thing that has ever happened to me. I would be lost without you."Justin and Hailey have had\u00a03 false startson a formal wedding celebration ... the dates weren't working for some of the guests so the "save the date" had to be scrapped 3 times. But, this time it looks like a go.\r\n\r\n\r\n\r\n\r\nJUSTIN AND HAILEY CRAZY IN LOVELAUNCH GALLERY\r\nWe don't know if the shindig will go down in the U.S. or Canada. Hey, we can't know everything.