The 2-year-old company plans to shut down Friday if it doesn't secure needed funding, according to its Web site.
Firetalk, a 2-year-old start-up, offers free and subscription-based services that allow people to talk online through their computers. The company, which competes against HearMe.com and Lipstream Networks, among others, also offers instant messaging and voice mail services and gives visitors of Web sites the ability to chat with one another.
"Like so many Internet start-ups that have been adversely affected by the difficult capital market environment, Firetalk Communications has been unable to secure additional funding for the continued operations of Firetalk," the company's Web site says.
Firetalk claims to have 2 million customers.
Firetalk executives could not be reached for comment Monday, despite repeated phone calls. The South San Francisco, Calif.-based company previously secured $45 million from earlier rounds of venture capital funding.
The company, which targeted consumers and businesses, said it plans to refund money to customers of its Firetalk VQ service, which offered unlimited phone calls over the Net, the ability to hold conference calls with up to 100 people, and other features. The service, available last fall, cost $19.95 for a six-month subscription.
"Although we have signed up thousands of VQ subscribers...the amount that we charged has been insufficient to cover the expenses for providing the service," the company's Web site says.
Firetalk is one of several free Web-based voice companies that have begun charging customers to help raise revenue. PhoneFree.com, which provided free domestic phone calls from PCs to regular phones, now charges consumers 2 cents per minute.