"I decided to come up to North Philly, where you can just get in and get out. I am mad!" said Blount, who lives in Strawberry Mansion.
She said she had no idea that the office on Cecil B. Moore Avenue had closed April 19.
Robert Smith, vice president at Beech Companies, which leased office space to the federal agency for about 10 years until the location shut down, said people are still showing up every day, unaware it closed.
"The first couple of days it was closed, there was a line of people waiting for it to open at 9 a.m., and when it got past 9 and it didn't open, some people started shaking the gates."
Workers from Beech came outside to hand out fliers to people who seemed puzzled.
One side of the flier, apparently prepared by the Social Security office, gave the address of the Center City office.
The other side advises people to call U.S. Rep. Chaka Fattah and U.S. Sens. Bob Casey Jr. and Pat Toomey.
Smith said Beech has asked Fattah's office to help get the office reopened. A Fattah spokeswoman said his office was told federal budget cuts - before the sequestration - is one reason the office was closed.
A spokesman for SSA said he couldn't respond to why people who regularly used the office were not notified that it would close.
Some people interviewed this week said they need to go regularly to an SSA office to get proof of income for subsidized housing, among other reasons.
North Philadelphia resident John Bass, 52, pulled up in a van in front of the office and said he also didn't know it was closed.
"I can't make it downtown," Bass said. "I can't afford the parking down there."
Robert Rooney, who lives near 12th and Market, said he always took SEPTA to the 15th and Cecil B. Moore office, because it was the only office he knew about.
Rooney, 40, said he got hurt operating a forklift in a South Philadelphia warehouse two years ago and now receives disability payments.
"I just spent money on SEPTA to come up here, and now I got to spend money to go back," Rooney said. He looked over a flier telling him there is another office in Center City and said: "I could have walked there from my house. I could have saved $4."
On Twitter: @ValerieRussDN