On Wednesday night, the society will be hosting an event at the Chapters Queensway to help raise money to ease the severe funding shortfall.
The financial strain began after the society opened a larger shelter at 67 Six Point Rd. in 2012.
Pia Lauretti, president of the Etobicoke Humane Society, told CBC Radio's Metro Morning the problem can mostly be traced to the increased demand for services.
"The cost of the facility really only increased the operating budget by a small percentage. We went from a retail space to an industrial space. But with all the media attention we got, with more volunteers coming, and with the Toronto community understanding we were there now, the demand for our services increased quite a bit," Lauretti said.
She said when it expanded, leaving a retail space and moving to an industrial space, the shelter was prepared to deal with increased demands.
"It wasn't a shot in the night move. We thought about it. We looked at the numbers.
"We didn't realize at the time, that once people became aware of where we were and that we were not affiliated with any other humane society — that we were in Toronto — we became more accessible to people and all of a sudden the numbers that we had predicted of animals being surrendered or abandoned to us were much higher than we had anticipated," Lauretti said.
Another problem is brand recognition. Lauretti said many people think the Six Point Road location is a branch of the Toronto Humane Society. That perception has led some donors to write cheques to the Toronto organization, believing the Etobicoke shelter will also be supported.
Despite its name, the shelter provides services to pet owners in the Greater Toronto Area, she added.
The Etobicoke shelter tries to do fundraising every month, to cover a rent of $5,000 and monthly veterinarian bills that range from $5,000 to $10,000.
"Right now we make under $200,000 annually, while the Toronto Humane [Society] brings in $10 million each year. There's a big big difference," Lauretti said.
To cover costs, the Etobicoke Humane Society is looking at increasing a donor base that would give on a monthly basis.