Telstra workers are being urged to reject a new wage agreement that their union warns offers a below-inflation pay rise for some and no guarantee of any rise for others.

Telstra will go directly to its employees to seek their endorsement in a ballot that opens on Monday.

Telstra chief executive Andy Penn. Credit:Peter Rae

A Telstra spokesman said "while the pay proposal is less than what Telstra employees have seen historically, importantly we are protecting our industry-leading terms and conditions to provide certainty over a period of significant change".

"We have proposed a pay increase of 4.5 per cent over the next three-year period. This includes a guaranteed pay pool of 1.5 per cent this year (and again in both 2019 and 2020)," the spokesman said.