(Telecompaper) The mobile network operators in the Netherlands are losing market share to new and low-cost providers, according to Telecompaper's latest 'Postpaid Mobile Insight' report covering Q1 2015. The combined share of the Vodafone, T-Mobile and KPN brands declined by 3 percentage points in the past year. Over the same period, Ziggo Mobile more than doubled its market share to 5 percent. In Q1 2015, 41 percent of postpaid customers had a subscription with a 'no-frills' provider, such as Telfort, Tele2 or Hollandnieuwe, up from 38 percent in the first quarter of 2014. The same trend was visible in the SIM-only segment (+2 percentage points), where premium providers have even less market share (41% versus 59% of the total postpaid market). Telfort remains the largest no-frills provider, although its market share has declined since the first quarter of 2014 by 3 percentage points. The report also shows that more than four in ten Dutch postpaid customers (44%) choose their mobile provider based on the monthly costs/fee; this is especially important for customers of 'no-frills' providers. This argument for choosing a mobile provider became more important in the past year. In contrast, the purchase price of the handset became less important, down by four percentage points compared to a year ago. This may be due to more consumers buying their handsets separately from their service plan. The report, based on a consumer survey, also found that Dutch consumers appear more satisfied with their postpaid providers. However, the market's NPS is still negative. The Net Promotor Score (NPS) has been gradually improving over the past year, from -10 to -1. The report also shows the pattern among SIM-only clients, where the NPS improved from -5 to -1 in 12 months.