Of the 20 worst bus routes across the Super City, 11 are in South Auckland where Auckland Transport trumpeted a simpler network, more buses and better fares last October.
On Waiheke Island, services between the Matiatia ferry and Onetangi and the wharf and O'Brien Rd have made the list of the 20 most-frequently late bus services compiled by the Green Party.
The Greens also said the data, for the period December 2015 to December 2016, showed the privately-run SkyBus to the airport turned up late almost one out of every five trips, or 18.3 per cent of the time.
This was contested by SkyBus director Adam Begg, who said the results showed that since taking over the business in late 2015 its punctuality had risen from 75.78 per cent to 92.69 per cent last month.
He said the improvements reflected investment in more buses, staff, additional kilometres and system improvements. SkyBus topped Auckland Transport's December 2016 customer satisfaction survey for the bus operators, he said.
A late bus is defined by Auckland Transport as a bus that leaves five or more minutes after the scheduled departure time. The information is collected from a GPS system in each bus.
Among the most punctual services are the 082 from Westgate to Te Atatu Peninsula and the 104 New Lynn/Avondale/New Windsor route at 98.35 per cent and 98.71 per cent respectively.
The Green's transport spokeswoman, Julie Anne Genter, said most Aucklanders wanted to see better, more reliable and frequent public transport.
Genter said the new South Auckland network was a great initiative, but council should have put in bus lanes before they created more services, some of which were meant to be every 15 minutes but were only every 30 minutes.
Three bus services - Mangere to Botany, Mangere to Sylvia Park and Papakura to Otahuhu station - were meant to be the most reliable and frequent and should be the priority for improvement, Genter said.
An Auckland Transport spokesman said given the level of construction in the city, it was happy with the performance of public transport. Bus services were at the best ever levels of service and ahead of target.
He said the statistics alone do not portray the entire situation, saying the link services were better measured between the gap between services rather than against the scheduled departure time.
This "headway" measure showed a delivery of about 85 per cent, compared to punctuality at 70 per cent, said the spokesman, adding "this is not as high as we would like though".
The spokesman said more work needed to be done on the number of bus priority lanes in the south and this work is continuing.
"Recently we introduced priority lanes for buses on Manukau Rd and Pah Rd," he said.
Genter said people gambled with the SkyBus, not knowing if it was going to take 30 minutes or an hour to the airport. The Greens support a continuous public transport route for the 21km trip between downtown Auckland and the airport - be it a busway, bus lane or rail.
Auckland Airport retail and commercial general manager, Richard Barker, said: "In the absence of public transport options, SkyBus, alongside our new line-up of taxi operators, offer cost-effective transport choices for our customers directly to and from the terminal forecourts."
Most unreliable bus services
The percentage of times the bus departed within five minutes of scheduled time
1. 399 Pukekohe to Port Waikato 35.71 per cent
2. 324 Mangere to Seaside Park 69.29 per cent
3. INN799 Inner Link 70.49 per cent
4. 31 Mangere to Botany 71.74 per cent
5. 323 Otahuhu to Panmure 77.5 per cent
6. 5 The wharf to O'Brien Rd 78.86 per cent
7. 313 Onehunga to Manukau Station 79.07 per cent
8. 32 Mangere to Sylvia Park 79.81 per cent
9. 309X Mangere to city centre 80 per cent
10. 2 O'Brien Rd to the wharf 80.43 per cent
11. INN798 Inner Link 80.85 per cent
12. 1 Maitiatia Ferry to Onetangi 81.50 per cent
13. Sky Bus, city to airport 81.74 per cent
14. 33 Papakura to Otuhuhu station 82.03 per cent
15. 1a Onetangi to Maitiatia Ferry 83.58 per cent
• Look up you bus below. Punctuality reflects the percentage of times your bus has departed within five minutes of scheduled time
