Ombudsman Judi Jones said while the increase in NBN complaints is not surprising given the growing number of connections to the network, the rise is concerning and the service is still not meeting expectations.
Other reasonably frequent issues were no service, problems with connections or changing provider, and poor service quality.
Speaking to the ABC, NBN co-chief customer officer Brad Whitcomb did suggest that this far along in the rollout it is important to both balance the customer experience and to ensure construction continues as necessary to meet the 2020 deadline.
"But there is a lot of work being done to improve the consumer experience which is great". Complaints from small businesses were at 9947 or 11.7 percent.
"In addition, we have made significant improvements to our processes and systems to minimise complaints".
"In percentage terms, these results are stunning".
Due to the way it has changed its complaints recording process as of July past year, the TIO also said it is "not possible to compare complaints at the service type and issue levels with previous reports".
The TIO is an industry-funded organisation that aims to help resolve disputes between consumers or small businesses and their phone and internet providers.
"The changes mean our data will more accurately reflect the description of complaints given by residential consumers and small businesses".
Complaints may involve more than one issue, but it does seem that providers are making a rod for their own backs by failing to deal with customers' complaints properly and promptly.
According to Jones, the TIO has also changed its service type categorisation for each complaint, with five categories: Mobile phone, internet, landline phone, multiple services, and damage or access to property.
While these changes aren't reflected in this six-month update, they could show a reduction in complaint numbers in the coming months, Ms Jones said.
The telecommunications complaints watchdog has revealed thousands of people have complained about the quality of service on the national broadband network (NBN), or have lodged complaints about issues with the installation of the service in their home. Complaints about mobile phone services (29.4%) and internet services (28%) were close behind.
That's nearly 30 per cent higher than the same time a year earlier.
Complaints were predominantly from residential consumers at 74,729 complaints, or 88 percent of the total.
And there has been a huge cut in average congestion, down to 18 minutes per week compared to almost 7 hours per week in March 2017.
Responding to claims by Telstra CEO Andy Penn that 5G will erode NBN's user base, Australian Prime Minister Malcolm Turnbull has said the volume of data being downloaded over fixed broadband will prevent this.
The TIO is clearly aware of that, as in its previous six-monthly update it observed that "The rate of increase in these complaints is slower than the rate of new premises connected to the national broadband network".
More Australians are being connected to the NBN than ever before and with this new service comes. a few bumps in the road.