The contract to keep the Spire clean for the next five years has been renewed at a cost of more than €420,000.
Dublin company Lynch Interact has been retained to ensure it will be maintained over the next five years.
The company has cleaned the Spire for the past three years and its current contract is due to expire this month.
The contract coming to a close had a tender value of €201,870.
The Clondalkin maintenance and engineering company was the only firm to submit an official tender.
Dublin City Council had put an estimated price tag of €450,000 on the new five-year contract, which has come in at €421,366.
The 120m tall Spire, which was installed to celebrate the Millennium, is located on the site of the former Nelson's Pillar on O'Connell Street.
It was completed in 2003 at a cost of €4.6m, and cleaning costs to date have totalled around €2.7m.
The Spire was originally touted as being self-cleaning as it was designed to allow rain to run off, taking any dirt away with it.
The contract covers the maintenance of the structure and all of the electrical, mechanical, monitoring and control systems.
Independent Dublin city councillor Mannix Flynn is a long-time admirer of the monument, but when the contract was put out to tender, he said: "You have to ask yourself in terms of value for money if the ongoing costs are justified? It's a huge price to pay for the city council."
Mr Flynn said there are many prominent businesses in that part of the city centre, and suggested the council should seek a corporate sponsor to cover the cleaning costs.
"It's a great piece of public sculpture without question, and it's very much loved by Dubliners. It's never vandalised," he said.
"When you look at it from the various angles, it's quite spectacular and sits very well in that location. It's such a huge piece of work and unique. It can never be compromised.
"You can't take away from the artistic merit that's there."
The Spire contract represents only a small portion of Lynch Interact's business.
The most recent accounts for the firm show it had revenues of €15.5m in 2018 as the company recorded pre-tax profits of €215,748.
It employed 75 people in 2018, when staff costs amounted to €4.3m.