A telecommunications commentator says Vodafone's decision to raise its prices is a sign the company is under pressure from its overseas parents.
The telco will be adding an extra $4 a month to the majority of its fixed home line and broadband plans, affecting about 300,000 households.
It followed a similar rise by Spark last month, when the Commerce Commission ruled Chorus should be charging phone companies more for its services.
Bill Bennett said last year was the first time Vodafone made a loss in 14 years and telecommunications overall was a declining market.
"All the telcos would be in struggling to make much more than very minimal profits, and what you're already seeing is a bit of a clawback."
Mr Bennett said the price rise would add about $15 million a year to Vodafone's revenues - half of the amount the company lost last year.