UPS customers who use the WorldShip software system to manage the sending out of packages can now opt to make the shipping process “carbon neutral”.

The company is extending its carbon offsets program to allow WorldShip customers in Europe, Asia and Americas to take part.

The move will mean more than 400,000 customers can choose to pay a small sum to counter carbon dioxide emissions arising from their shipments.

Emissions levels are calculated using current and historical operational data, UPS said, including distance and type of transport.

Fees collected from the service are used by UPS to buy carbon credits, with the funds ultimately supporting environmental projects such as the operation of renewable energy generating facilities.

As with its 2009-2010 carbon offsets program, UPS has also pledged to match customer offsets up to $1 million in order to extend the benefits of the offering.

Alan Gershenhorn, senior vice president of global sales and marketing, said: “This product was developed in response to customer demand for environmentally responsible shipping options. Now UPS carbon neutral will be accessible to the majority of our customer base.”

WorldShip is a Windows-based shipping software suitable for customers shipping five or more packages each day. The system can help generate shipping labels and forms, manage billing and accounts and send out email notifications.

UPS said there has been more than 550,000 installations of the software worldwide.

UPS has its offsetting program certified by The Carbon Neutral Company, while its calculation methodology for the new WorldShip offsets has been verified by Societe Generale de Surveillance (SGS), based on the international carbon accounting standard, the Greenhouse Gas Protocol.

Previously, UPS offsets have funded projects including landfill gas management in Colombia and China, a forestry project in California and a renewable biogas energy project in Thailand.

As well as WorldShip customers, UPS also offers carbon offsetting for its shipping systems UPS Internet Shipping, UPS CampusShip, Host and Vendor Solutions, UPS Developer Kit, iShip and ConnectShip.

Carbon offsets have been offered to customers paying daily rates with per-package fees of, for example, between five cents and 75 cents in the US and between 10 cents and 55 cents in Europe, depending on the delivery service required.