The platforms at Essex Road station are being spruced up – and the old tiles have been replaced.
Govia Thameslink Railway (GTR) is carrying out the redecoration programme. The operator said bright new tiles would replace two layers of "old and stained" ones on the walls, as they have at Moorgate further along the Northern City line.
The new look will be white walls with a black strip along the bottom, with blue tiles at corners.
Workers removed more than 4,000 sacks of rubble as work got underway at the weekend. It is set to be completed by the end of April.
Old Street and Highbury and Islington stations will also have tiles replaced.
GTR's managing director Tom Moran said: "Islington's stations on the Northern City Line have been overlooked for years when it comes to investment so I'm delighted we will be smartening up every station on the NCL over the next few months.
"Passengers are now benefiting from the brand-new fleet of air-conditioned trains we introduced last year. This investment is about making sure our stations are also up to the standard passengers expect."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here