The company attributes its continued growth to the market shift towards email outsourcing and the desire to work with an email specialist for such mission critical business communications.

"Email is the most widely used communication medium in business," says Pat Matthews, CEO at Webmail.us. "Businesses rely on email, but a growing number of them don't want to manage it themselves. They turn to us because we're specialists--we're 100 percent focused on hosting email for our customers."

The company's comprehensive email services include support for POP3, IMAP4, and SMTP protocols, shared calendaring, anytime, anywhere access to email, contacts, calendar events, tasks and blog feeds, large attachment size limits and huge mailboxes, built-in anti-spam and virus protection, email marketing tools, Webmail Mobile, control panel and around the clock, live customer service and support.

Webmail.us announced last month it joined the Email Sender and Provider Coalition and the Messaging Anti-Abuse Working Group.