The Category 5 storm, which ravaged the islands with near-record, sustained 185mph winds, battered an estimated 1.2 million people.
Irma cut a devastating path, leaving at least 44 people dead in its wake; 11 in the French territories, 10 in Cuba, five in the British Virgin Islands, five in the US Virgin Islands, four in Anguilla, four in St. Maarten, three in Puerto Rico, one in Haiti, and one in Barbuda.
The scale of destruction was steep.
One week since the massive storm made landfall, here's where things stand in the Caribbean.
Two men search through the rubble of their St. Martin restaurant on September 10.
Anguilla, Barbuda, the British Virgin Islands, St. Martin / St. Maarten, the US Virgin Islands, and Turks and Caicos were hardest hit, with up to 99% of structures at least partly damaged.
On Wednesday, the eye of the storm passed directly over the island of Barbuda, leaving the underdeveloped oasis barely habitable. The UN's Office for the Coordination of Humanitarian Assistance (UNOCHA) said 99% of all buildings in Barbuda had been destroyed. There is no electricity or water service on the island.
In Cuba, 13 of the country's 15 provinces have been affected. Although flood waters are receding in Havana, flooding in other coastal and mountain areas have left some communities isolated. Fresh water supplies have been contaminated in the north, according to the UNOCHA.
People salvage material from the remains of a house in Isabela de Sagua, Cuba, on September 11.
The storm's damage also threatens Cuba's food security, with key agricultural crops like plantains, rice and sugarcane damaged and food storage areas isolated or destroyed by flooding.
On Anguilla, a 90-square kilometer island that is among several British overseas territories in the Caribbean, 90% of all government buildings were severely affected and 80-90% of the island's schools have been damaged, the UNOCHA said. Electricity and phone lines have been disrupted, hospitals have limited capabilities and there is no running water.
On St. Martin / St. Maarten, an 87-square kilometer island split into territories administered by France and the Netherlands, authorities on the French side estimate 60% of homes are uninhabitable.
A sailboat rests in a cemetery after Irma tore through Marigot, St. Martin.
In the British Virgin Islands, 90% of the houses on the North Sound have structural or total damage. In the Spanish Town, 75% of the homes have been damaged. The island's water systems have been significantly damaged and electricity is scarce.
Infrastructure has been severely damaged on Turks and Caicos, a British overseas territory home to about 52,000 people, after Irma barreled through overnight Thursday into Friday.
There is no electricity, bottled water is limited and damage at a water treatment plant has halted distribution of drinkable water. On South Caicos, 80-90% of homes have been damaged; schools, government buildings and hospitals have been badly hit.
British army commandos provide assistance on the island of Tortola.
The UK, France, and the Netherlands have stepped up relief efforts, sending thousands of troops and promising aid packages after criticism they responded too slowly.
The UK government has pledged £57 million ($75 million) in aid. Prime Minister Theresa May announced on Wednesday that the UK would deploy an additional 200 personnel and 60 police officers on top of 40 tons of aid and 1,000 military personnel already sent to the region.
The UK had a naval vessel, Mounts Bay, preloaded with disaster relief supplies in the Caribbean since July, and within a couple of days had restored electricity at Anguilla's hospital and cleared the airport runway.
French President Emmanuel Macron said his government had mounted one of the biggest airlifts since World War II. Some 85,000 tons of food and 1 million liters of water have been deployed to St. Martin and St. Barthelemy.
French firemen provide bottles of water to residents of Marigot, St. Martin, on September 10.
US President Donald Trump approved and signed a disaster declaration for the US Virgin Islands, unlocking $223 million in emergency federal funding. Trump also declared a major disaster in Puerto Rico, ordering federal aid to supplement local recovery efforts.
On Wednesday, Cuba received 7.3 tons of humanitarian aid, including mattresses, water, canned food and other vital supplies, from the Venezuelan government, according to the state news agency.
People make their way through debris in the Cojimar neighborhood of Havana on September 10.
NGOs like the Red Cross and Unicef have stepped in. But in dozens of messages sent to CNN via text and WhatsApp, many have said the aid provided so far just isn't enough.
Some 200,000 people are in need of aid in the eastern Caribbean, including Anguilla, Antigua and Barbuda, and St. Martin, according to the World Food Programme.
French soldiers patrol in the Bay of Nettle area of Marigot on St. Martin on September 12.
Looting has broken out on some islands. France's Overseas Minister Annick Girardin said she saw people stealing televisions from shops. Other residents have described fights at grocery stores and gas lines.
Macron vowed that the overseas departments would return to public order soon. But St. Martin residents interviewed by CNN affiliate BFMTV said that French police and soldiers have had little presence on the ground, and reported widespread looting.
French President Emmanuel Macron shakes hands with residents during a visit to St. Martin on September 12.
The Netherlands also deployed additional troops to contain what Prime Minister Mark Rutte described as "serious" post-storm looting on St. Maarten.
On the British Virgin Islands, more than 100 inmates escaped in a prison break during the chaos of the storm. It was not clear whether the prisoners had been caught.
Early economic estimates place the financial cost of Irma's destruction at around $10 billion across the affected islands, according to the UNOCHA.
People inspect the damage to the Grand-Case Bay beach on St. Martin on Tuesday.
In 2016, parts of the Bahamas, Cuba and Haiti were torn apart by hurricane Matthew -- also a category 5 storm. Two hotels on Grand Bahama are still closed, leaving many residents still without work.
If history is a guide, many islands in Irma's path can expect to encounter similar hardships.
In St. Martin and St. Barthelemy, the French reinsurance body CCR has estimated a 1.2 billion Euro loss ($1.44 billion USD).
On Barbuda, a fairly underdeveloped island home to a few luxury hotels, early estimates place the damage at around $100 million.
In Havana, Cuba, the cleanup effort has slowly begun.
Many of Cuba's luxury hotels on the north coast -- key in its expanding tourist market -- were hit hard, but state media reported on Monday that hotels will be open and ready for guests in time for the season.
Cuba's agricultural industry has suffered significant losses, with state media reporting severe damage to livestock, fields, factories and warehouses. Flooding has damaged the country's sugar plantations -- sugar is one of its biggest exports.
State media reported over 71,000 chickens perished in the