In two new polls published on Friday, the party received support from 8.2 percent and 6.1 percent of voters.
Support for the Social Democrats, however, continues to trend downward in both polls. Sweden's largest political party now has support from 27.9 percent and 26.2 percent of voters.
The Moderate Party, which currently leads the centre-right coalition Alliance government, has seen poll numbers drop in recent days as well, as has the Left Party.
According to the latest poll by the Sifo, the results of which are published in the Svenska Dagbladet newspaper, the Pirate Party received support from 8.2 percent of voters, which is enough to give it two seats in the European Parliament.
The party's support has grown by 2.2 percent since the previous poll, which is a statistically significant rise.
The 3.8 percent drop for the Social Democrats, which brings the party's overall support to 27.9 percent, is also statistically significant.
The overall Sifo poll results are as follows, with the change from the previous poll in parentheses:
Left Party: 6.0 percent (-0.5 percent); Social Democrats: 27.9 (-3.8); Green Party: 10.9 ( +0.7); Centre Party: 5.1 (-0.1); Liberal Party (Folkpartiet): 11.4 (+1.3); Moderates: 21.3 (-1.3); Christian Democrats: 4.4 (+1.3); June List: 1.7 (-0.2); Pirate Party: 8.2 (+2.2).
The poll was carried out between May 25th and June 3rd, and is based on interviews with 1,897 people.
In the last poll by Synovate before the election, the Moderates and Social Democrats lost the most support, with the latter polling at 26.2 percent, down from 30.3 percent in Synovate's previous poll.
The Moderates, meanwhile, saw their support fall from 26.3 percent in May to 22 percent, according to the poll results, which were published in the Dagens Nyheter (DN) newspaper.
The overall Synnovate poll results are as follows, with the change from the previous poll in parentheses:
Left Party: 5.0 percent (-1.0 percent); Social Democrats: 26.2 (-4.1); Green Party: 11.0 (+1.9); Centre Party: 6.2 (+0.5); Liberal Party (Folkpartiet): 10.9 (+1.9); Moderates: 22.0 (-4.3); Christian Democrats: 6.2 (+1.5); June List: 2.9 (+1.4); Pirate Party: 6.1 (+0.7).