Lalaine Agtarap, 50, of Figtree, used her job as a data entry clerk and administration officer to steal more than $3.79 million from the social housing organisation in 245 illegal transactions between November, 2006 and April, 2013, according to a draft set of facts tendered during committal proceedings on Wednesday.

Agtarap disputes the amount stolen, but has admitted to thefts totalling more than $2.8 million and pleaded guilty to a charge of stealing property as a clerk/servant.

According to a 12-page statement of admissions, Agtarap changed the data on The Housing Trust's online banking system so payments intended for internal transfer, or transfer to a third party, flowed to her bank account.

The thefts succeeded even though two managers had to enter approval codes in order for the transactions to go ahead.

"They would simply enter their code after checking the total value of the transaction, they did not appear to check to whom the payment ... was going to be made," Agtarap said in her admissions.

"I expected to be caught when The Housing Trust's accounts were audited for the 2006-07 year but when I was not caught; I increased the frequency and amounts I was taking.

"Much of the money that I misappropriated, I gambled."

Agtarap's losses included $60,000 during a single visit to Star City, where it was her habit to play the maximum bet of $100 per spin.

Twice she had wins of more than $100,000 at Wests Illawarra.

"When I did win, I would usually not deposit my winnings back into my accounts but would hold on to it as cash and gamble it," she said.

Agtarap calculated net losses from her gambling totalled about $1.39 million - the end result of many more millions passing in and out of the pokie machines.

"Having now seen the records from three locations where I gambled, I now see that I have used the money I misappropriated from The Housing Trust to gamble and the winnings from my gambling I used many times over to gamble even further," she said.

Agtarap's spending in the statement of admissions shows:

According to a draft set of facts tendered to the court, the stolen money was directed to Agtarap's personal CBA account in the name of Lalaine Marie Agtarap trading as Pick N Clean Services.

Pick N Clean, one of Agtarap's two businesses, provided cleaning and mowing services to The Housing Trust.

The court heard the Philippines-born Agtarap would use some of the stolen money to cover expenses associated with this and her second business, Triple R Asian Grocery.

She also sent money to relatives in the Philippines including her brother, who also had a gambling problem and had mortgaged his home or pawned belongings to support his habit in the past.

Agtarap was escorted out of The Housing Trust's offices in April 2013, after meeting with the financial manager and chief executive officer over the suspect transactions.

She resigned soon after, ending almost 20 years of employment.

She repaid $45,000 with an initial bank cheque, and later agreed to forfeit her statutory entitlements as partial repayments, and at the time of her admissions her repayments totalled $77,000.

Agtarap cut short a holiday to the Philippines in May 2013 after she received a summons from the Supreme Court of NSW, where separate proceedings are under way in the equity division.

The matter has been adjourned to Sutherland District Court August 21 for sentence.