The best replacement for billings is bookings.

The best alternatives to billings are rated as following:
★★★★★  bookings
★★★★  bozeman
★★★★  harvest
★★★★  ibiz
★★★★  pearson
★★★  on the job
★★  mostel
★★  missoula
★  great falls
★  macfreelance
★  profittrain
★  freshbooks
★  creighton method
  billings
  officetime
  invoice2go
  net billings

Your alternative for billings is not listed? Suggest!
Speaking about billings, one probably shouldn't forget about daylite.

Other search terms related to billings and their ratings are:
★★★★★ daylite
You have in mind a companion for billings and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of billings in all years. Click on graph for more.
billings
bookings
bozeman