AP Photo/Michael Probst
President of European Central Bank Mario Draghi waits for the beginning of a news conference in Frankfurt, Germany, Thursday, Jan. 22, 2015.
It means any banks that want to deposit cash with the ECB will actually loose money, rather than earn interest. The measure is meant to encourage banks to lend cash out rather than hold on to it. That in turn will boost growth - that's the idea anyway.
The ECB's decision to hold rates was widely expected by the global markets, following the decision by the bank's governing council to cut rates at its last meeting in December 2015.
While the hold doesn't come as a surprise, markets in Europe and across the world will be waiting with bated breath to hear what ECB president Mario Draghi says when he steps up to take questions from the press at 1:30 p.m. GMT (8:30 a.m. ET). According to an ECB press release, Draghi will "comment on the considerations underlying" the bank's decision to hold rates at the press conference.
It's also thought that Draghi might address the threat of low inflation within the Eurozone at the press conference.
The ECB predicted in December that inflation would average 1% during 2016, but inflation within the Eurozone currently sits at just 0.2%, and some, including Barclays, are predicting it will fall as low as 0.1% this year. The oil slump is a big driver.
Draghi will likely also touch on the impact the oil price slide and China's slowing growth on European stock markets in recent weeks.
Thursday's rate decision went a lot more smoothly than at December's deposit rate announcement when a false report from the Financial Times that the ECB had left rates untouched was accidentally published nine minutes ahead of time. It shocked markets and sent the euro spiking.
Then, the ECB's actual decision was to push its deposit rate even further into negative territory, cutting from -0.20% to -0.30%
At the same time as announcing the unchanged deposit rate, Europe's central bank also left its refinancing rate untouched at 0.05%, once again meeting market expectations.