Britain's Prince Harry sued the Daily Mirror, Sunday Mirror and Sunday People newspapers for phone hacking and illegal activities.
In December, the High Court ruled that Harry was the victim of "unlawful information gathering", including the hacking of his phones with the knowledge of editors.
However, it only considered 33 of the 148 articles Harry complained about and ruled in favor of the prince in 15 of them.
David Sherborne, the prince's lawyer, told the court today that the Mirror newspaper had admitted the rest of the charges.
"Mirror Group Newspapers will pay the Duke of Sussex a substantial additional sum in compensation," Sherborne said.
FIRST ROYAL TO TESTIFY IN 130 YEARS
Prince Harry, who became the first British royal to testify in court in 130 years when he appeared in June, initially received around $180,700 in damages after the judge ruled that he had been unlawfully targeted by the newspaper.
Prince Harry was one of around 100 plaintiffs - actors, sports stars and celebrities - who sued the newspaper.
The complaint by Prince Harry and three others was selected as a test case.
The prince's lawyer said the newspaper would likely pay more than £2 million to cover the plaintiffs' legal costs and an interim payment of £400,000 for the prince's individual costs.
Prince Harry was not in court during the hearing as he was traveling to England to see the king after his father King Charles was diagnosed with cancer.
