Thomas White, 26, took over the running of the notorious dark web site Silk Road after it was first closed in 2013.
After he was jailed for over five years in 2019, officers at the NCA continued to investigate his finances.
After the original Silk Road site was shutdown by the FBI, White launched Silk Road 2.0.
Like the original site, it used technology to allow users to anonymously buy and sell class A and B drugs, computer hacking tools and other illegal goods, using the digital currency bitcoin.
When officers examined his electronic devices after his arrest, they also discovered a stash of child sex abuse images.
At a recent confiscation hearing at Liverpool Crown Court, White was ordered to repay £493,550.00 from his bitcoin holdings. All electronic items used by White in the commission of the offences were also forfeited.