ICv2 claims that comics and graphic novel sales increased by 18.6% compared to the same period last year, with further growth predicted.
The retail news and analysis site also pointed out that comic sellers invested $223 million (£143m) in the direct market throughout June, marking an increase on July last year.
ComiChron market analyst John Jackson Miller believes that the next six months will see further growth, as the latter half of the year traditionally outperforms the first by around 10%.
Marvel Comics led the market share by the narrowest of margins in June, edging out DC Comics with 33.77% to 33.03%.
Avengers vs X-Men took the top two spots in the single issues, while DC's Before Watchmen occupied places five to eight. The Walking Dead Vol. 16 was the bestselling graphic novel.