The latest addition follows the launch of 24 new buses in September, and the launch of a mobile ticketing smartphone app which lets customers buy travel tickets on the go.
The second fleet of buses, which are now running on routes 30 and 31, form part of a wider programme of investment by the company, further demonstrating its commitment to giving passengers an enhanced travel experience.
Following the launch of its app earlier this year, Stagecoach North East aims to develop its technology with the introduction of smart, multi-operator ticketing and an improved website.
The bus firm unveiled its mobile ticketing technology with a series of app demonstrations across the north east, and has committed to delivering contactless payments in Tyne and Wear by the end of the year.
Over the past five years, Stagecoach North East has invested heavily in improvements for customers including introducing more than 240 new vehicles, worth £37m, for local communities.
Steve Walker, managing director at Stagecoach North East, said: "We continually look towards enhancing our fleet and we hope the addition of 18 new buses in the region will significantly improve the travel experience we offer our customers in Newcastle. With increased congestion and traffic on our roads, as well as offering a cleaner and greener way to travel, buses now provide an increasingly vital and efficient service for our passengers.
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