Further expansion occurred during World War II, where Bunnings co-operated with its rival Millars, and in the post-war period which saw the creation of a workshop in Manjimup and timber mills in south-west Western Australia and north Queensland.

[12] Present at the official opening were the Victorian premier Jeff Kennett, American actor Richard Karn[citation needed] who played Al Borland on the television sitcom Home Improvement, and Joe Boros, the managing director of Bunnings.

In August 2001, Wesfarmers bought the Howard Smith Group, including BBC Hardware (previously Nock & Kirby) and big-box offshoot Hardwarehouse.

In 2008 the Australian Competition & Consumer Commission (ACCC) looked into its acquisitions of five Mitre 10 stores, as it deemed the purchases would be anti-competitive.

In February 2009, the ACCC allowed the purchases, finding that the acquisition of the Mitre 10 stores did not significantly alter the level of competition in the relevant market.

[25] In mid-May 2020, Bunnings announced it would close seven stores in New Zealand in Ashburton, Hornby, Hastings, Cambridge, Rangiora, Te Awamutu, and Putāruru with the loss of 145 jobs as a result of the global COVID-19 pandemic.

[28] In Australia, Bunnings unsuccessfully lobbied the Victorian state government to exempt its 168 stores from closure during the second Melbourne lockdown.

[31] The ACCC ruled that the purchase of Beaumont Tiles outlets would not reduce competition as Bunnings was not currently in the field in a big way.

[32] In November 2021, both Bunnings and Officeworks partnered with the Flybuys Loyalty program to allow customers to collect points at both stores.

[33] In 2022, Bunnings sought to expand its commercial business by doubling the number of frame and truss processing plants it owns from three to six by 2024.

[34][35] In 2023, Bunnings expanded its pet care and cleaning product ranges, reflecting the company's repositioning as a home improvement destination.

[36][37] In early 2024, Bunnings temporarily rebranded one store in each Australian state and in New Zealand to "Hammerbarn", a fictional hardware shop in the animated television series Bluey.

The in-store services include a hire shop, spare parts enquiry, colour matching, key cutting, pool water testing and gas swapping.

Bunnings also provides gardening, craft, and woodwork do it yourself (DIY) workshops for children in-store, as well as for other groups in schools, nursing homes, and hospitals.

On weekends (and weekdays at some sites), Bunnings outlets regularly host sausage sizzles and cake stalls for community groups and causes.

[45] In February 2016, Bunnings' parent company Wesfarmers bought the United Kingdom-based hardware chain Homebase for £340 million.