Twelve per cent of the Hastings total (almost $10m) came from Napier shoppers, up 15 per cent on the same quarter last year, while just over 5 per cent of the Havelock North total (almost $2m) came from Napier cardholders, up 8.7 per cent.
Central Hawke's Bay shoppers also made a significant contribution to the Hastings figures, spending more than $5.6m over the three months, 20 per cent up on the same period last year.
Spending by people from outside Hawke's Bay, including international visitors, was also up in both areas.
MarketView based its reports on electronic card transactions with adjustments made to allow for cash and hire purchase payments.
Hastings District Council's economic development and urban affairs committee chairman Damon Harvey said the results continued the trend of the previous 15 months and confirmed that the district's economy was performing strongly.
"This extended growth period, in which we have outperformed the national average in every quarter for almost the last two years, is very good news on a number of fronts.
"As well as being good for retailers, it is confirmation that our economy as a whole is in excellent shape.
"A good part of that is because we have a very good spread of business across a range of fields so some of the economic shocks that have affected other parts of the country, such as dairy downturns, don't have any serious implications for our district."
Mr Harvey said one of the obvious factors was having more people in the central city area, which enhanced the atmosphere, which in turn led to more people enjoying the space and spending more time there.
Hastings City Business Association general manager Susan McDade said bigger things could be expected in coming years.
"Things are still looking positive for Hastings with an increase in spending from Napier customers of another 15 per cent. I would hope the growth of the last few years would increase event more with the reopening of the Opera House and the other developments in Hastings."
Havelock North Business Association president Jane Mackersey said Havelock North businesses overall, started 2018 feeling very positive after a strong last quarter.
"This stunning summer we are experiencing is great for visitors to the region, as they leave with a strong desire to return to stay-play-eat-shop.
"The HNBA will continue to focus on encouraging more spending in the village from outside the region by helping promote events in and around the village and Hawke's Bay."