Free admission to Tauranga swimming pools for children and young teens would cost ratepayers an extra $450,000 to $550,000 a year - or up to $13 for each household.
The size of the potential subsidy - if Tauranga City Council followed Auckland's example and made entry to all the city's pools free from next year - was disclosed by Tania Delahunty, the chief executive of Tauranga City Aquatics Ltd (TCAL).
TCAL director and deputy mayor David Stewart said free admission for children was talked about a few years ago but the idea did not gain much traction.
Rates would not only need to increase to cover the drop in revenue, but the council would be unable to build new pools, or pay for Baywave, he said.
Subsidies for swimming pools this year stood at $850,000 - up nearly 15 per cent on last year.
Councillor Stewart said the council's policy was to make swimming as affordable as possible. Increasing the subsidies could be at the expense of new facilities in the future.
He likened the pools to the construction of TECT Arena at Baypark, where the council had to reach agreement with users for higher fees in order to make the arena affordable.
"It is a matter of trying to strike the right balance between ratepayer subsidies and user fees. But more importantly, what would it mean for the future? We could not keep up with the demand for new facilities."
The balance between subsidies and user fees was to ensure no one was penalised by not being able to afford the cost of a swim.
Ms Delahunty said a quick calculation, based on the number of pool users last year, was that free admittance for under-16s would impact by about $450,000 to $550,000 on rates. Under-2s were already free in Tauranga.
However, her calculation did not consider a variety of discounts and the impact on family tickets. The upside of free admittance was that the greater numbers would lift the secondary sales like the Baywave hydroslide, learn-to-swim and the cafeterias.
The move in Auckland has been driven by the former Manukau Council not charging admission for adults or children to its pools.