Iran has been offline for more than 100 hours, London-based internet monitoring group NetBlocks said on Monday.
The group said national connectivity levels remain at around 1% of normal, according to a post on the US-based social media company X.
Iran has been rocked by waves of protests since last month, beginning on Dec. 28 at Tehran's Grand Bazaar over the sharp depreciation of the rial and worsening economic conditions, before spreading to several other cities.
US-based rights group HRANA has reported 490 protesters and 48 security personnel killed, with more than 10,600 people arrested, though no official casualty figures have been released.
