Boston Public Schools spent $857,000 of public money improperly or through practices that violated Massachusetts procurement law, according to the state’s inspector general’s office.

The scathing report released Wednesday found that school employees repeatedly hired vendors without valid contracts or the required competitive bidding, then devised a workaround to pay them later. The report examined conduct from 2018 through 2024.

Massachusetts Inspector General Jeffrey Shapiro told WBUR that investigators did not find evidence of fraudulent activity or criminal conduct. But poor department oversight and informal vendor arrangements wasted money that could have supported students.

“There’s wasted money,” Shapiro said. “You probably have at least $200,000 that could have gone to programs that more directly affect students.”

District employees routinely routed payments to vendors through a handful of companies with existing district contracts, essentially using them as middlemen to pay other vendors. Some charged mark-ups, costing the district at least $77,000 in added fees.

Boston also paid extremely high, sometimes duplicate, shipping charges on books. One $96 invoice for four books carried a $211 shipping charge, more than twice the price of the books themselves.

“These four books were shipped from Multicultural Book World to the BPS administrative offices, both in Roxbury, and three blocks apart,” the report reads.

But the charge passed through the district’s payment process without being flagged by the employees who reviewed invoices or their managers, who should have maintained adequate oversight.

The report comes within weeks of the first day of school, as declining enrollment and rising costs place mounting financial pressure on Boston Public Schools, which earlier this year cut staff to balance its budget.

District leadership in a statement said that the department has reformed its business practices, removed individuals and hired new operations leaders.

Shapiro said the findings were serious and so “unusual” that he told BPS to halt payments on vendor contracts for non-essential goods and services for 10 business days. He recommended that the district conduct an immediate investigation to review the contracts.

A spokesperson for the district said in a statement that BPS will implement the recommended 10-day pause.

Shapiro also strongly recommended Mayor Michelle Wu and School Superintendent Mary Skipper each appoint a senior official to oversee an immediate assessment of the district’s Division of Operations. The Inspector General, however, cannot compel the district or Wu to follow the recommendations.

Wu’s office did not immediately respond to requests for comment.

Boston City Councilor Erin Murphy blamed the failures on city leadership.

“It’s disturbing to see that we couldn’t get this right,” she said. “The buck always stops at the top.”

Murphy said Skipper must explain how these practices were allowed to continue.

“It wasn’t just one incident, it had to have been several incidents happening time and time again. It almost seems like it’s just a way they’re doing business,” she said.

The investigation also found instances when the district avoided holding a competitive bidding process, hiring some vendors without seeking quotes or bids for purchases of $10,000 or more.

In one example, the report says employees created a sham water testing procurement and steered it to Envirotrac instead of trying to find the best-priced vendor. The actual purpose allegedly was to pay outstanding bills, including old invoices from another company.

The investigation began after the inspector general’s office received multiple complaints, according to the report.

But the report wasn’t the first time Boston Public Schools were warned about their procurement practices. The Boston Finance Commission raised related concerns in 2023, and provided additional information in 2024. But the district took “little to no action” to address the problem, according to Shapiro.

“The same kind of behavior continued,” he said.

Eve Zuckoff contributed to this report.