That was an 18 per cent increase on the same period in 2016, when 152 such properties sold.
It's a slight drop from the record levels hit in the second half of last year, when 199 Bay properties sold for over a million.
Tauranga had the lion's share of the high-end market this year, accounting for 140 of the 180 sales between January and June - an 11 per cent increase on the same time in 2016.
The Western Bay had 26 sales, Rotorua 14 and Whakatane 6.
Nationwide, the number dropped 4 per cent mostly driven by Auckland, which saw an 8 per cent drop.
Excluding Auckland, sales were up 16 per cent throughout the rest of New Zealand.
Some regions saw record numbers of million-plus sales: Hawkes Bay, Nelson, Taranaki, Tasman, Waikato and Wellington.
Simon Martin, managing director of Harcourts New Zealand, said the top end of the market had not really been affected by loan to value ratios.
"Demand is still reasonably strong in that bracket, and with prices increasing over the last three or so years more properties have been pushed into that bracket. A property that was $900,000 two years ago would be over $1 million now."
He said people buying in the lower end of the market - first-home buyers and property investors - were harder hit by the ratios.
Asked why the Bay was growing as Auckland sales dropped, Mr Martin said there had been growth in people coming to Tauranga and purchasing top-end properties.
Realty Group chief executive Simon Anderson said in the first quarter of the financial year the group, which includes the Bayley and Eves brands, sold twice as many homes over a million dollars as last year.
That went against the trend for the overall number of sales.
"It shows that buyers at that stage of the market have ready cash."
The decrease in big Auckland sales was no surprise, and the Bay's increase was probably a flow-on effect.
"We're still getting a lot of inquiries from people in Auckland, as well as Wellington and, of course, our local buyers."
He said the upcoming election could impact the market, adding an element of uncertainty that may play on the minds of people buying or selling.
In the year to June four Bay of Plenty properties sold for over $3 million and one fetched over $5 million.
Realty Group had the only sale over $5m in the period, for an Ocean Beach Road property in Mount Maunganui.
- Bay of Plenty: up 18% to 180
- Tauranga: up 11% to 140
- Western Bay: up 8% to 26
- Auckland: down 4%
- NZ: down 8%
- NZ excluding Auckland: up 16%