The acquisition is the second since the group agreed a new three-year £20m facility with Lloyds Banking Group in February, following the May purchase of Lane Packaging for an initial £700,000 (rising to £1.1m subject to performance).
Macfarlane Group stressed that the acquisition of Network Packaging, including its sister company Network Display, was not conditional on the £3m capital raise, which will be achieved via the issue of 8m new Placing Shares at 37.5p each to institutional investors.
Group chief executive Peter Atkinson said: "The Placing is a general raising of funds to support future acquisitions and to make sure we have the right balance of equity and debt in the business."
He added that the placing was in response to shareholder demand, after shareholders indicated that they would support the raising of capital to fund the group's acquisition strategy.
Atkinson said that the group would continue to target good quality profitable businesses in the £3m to £12m revenue range that fill a geographical gap or improve market penetration, with its next acquisition likely to come in the first quarter of 2015.
"Network Packaging is a very high quality business with a high quality management team that operates in areas in terms of third-party logistics and internet retail that are complementary to the areas Macfarlane operates in," he added.
Network Packaging's Wolverhampton site will join Macfarlane's 16 existing UK sites and service an area stretching north towards Stoke-on-Trent and west towards Telford.
"Wolverhampton is a good location for us because we have a site in Coventry that covers the area to the south, while the Wolverhampton site will cover areas north of there, towards the Potteries and across to Telford," said Atkinson.
Commenting on Network Display, the bespoke POS and retail display packaging arm of Network Packaging, Atkinson said that there could be synergies with Macfarlane's own POS division and that the group would evaluate all options for the business.
Network Packaging recorded an EBIT of £800,000 on revenues of £7.8m in 2013, although a research comment from Arden Partners on the acquisition predicted an increase in EBIT to nearer £900,000 in 2014.
Arden added that Network Packaging fell into Macfarlane's acquisition "sweet spot" of good quality businesses with "an established and complementary customer base".
Macfarlane Group's shares were up 1% at 40.15 at the time of writing.