Sheffield Crown Court was told how on February 21 this year, a single mum living at a house in The Homestead, Bentley unlocked her front door at around 6.25pm, expecting her partner to arrive at the property after finishing work shortly after.
He arrived home at around 6.30pm, while the woman and her son were upstairs.
Shaun Sanderson, 37, crept into the house a matter of minutes later.
Prosecuting, David Wain, said: "They heard a door creak. The woman's partner went downstairs and couldn't see anything amiss, but the front door was open.
"Her purse was missing that contained her bank cards.
"She checked her account, and there had been a withdrawal made at Tesco.
"The defendant withdrew £100 and was caught on CCTV."
The court was told how the woman had left the pin number to her bank account with her bank card in her purse, which is how Sanderson, of Elm Green Lane, Conisbrough was able to withdraw money from a cashpoint.
In a victim impact statement the woman told the court how the burglary meant she no longer felt safe in her own home.
She said: "I live alone with my three-old-son. I'm a single parent and cannot afford to have lost that money.
"I transferred the money for a trip. I don't want to live here anymore."
The CCTV led to Sanderson being arrested in connection with the burglary on March 1, and under police interview he initially told officers he had withdrawn the money but said the bank card had been given to him.
He admitted to the burglary at this morning's sentencing and to one count of fraud, relating to the use of the woman's bank card, at an earlier hearing.
The court was told how Sanderson had committed 71 offences from 27 previous convictions, many of which were for burglary.
Defending, Cheryl Dudley, told the court that at the time of the offence Sanderson and his partner were living in a shed, which had led to them both developing health problems.
Ms Dudley said he had not been offered accommodation or support during his recent release from prison, which had led to him being homeless.
She added that Sanderson was 'remorseful' for his actions.
Judge Roger Thomas QC sentenced Sanderson to two years and six months in prison.
He said: "This young woman had her three-year-old with her and had left the door unlocked knowing her partner was coming back from work.
"You took advantage of that and stole her purse and used her pin number to withdraw £100.
"You have to think about the effect you have had. This was a young woman who had saved that money up. She had a trip to make, but couldn't do it because you took it."