(3)SIGNIFICANT CLIENTS AND OTHER CONCENTRATIONS

The Company had one client that contributed in excess of 10% of total revenue for the six months ended June 30, 2026; this client operates in the automotive industry and is included in the TTEC Engage segment. This client contributed 12.1% and 10.7% of total revenue for the six months ended June 30, 2026 and 2025, respectively. In addition, the Company has other clients with aggregate revenue exceeding $100 million annually and the loss of one or more of these clients could have a material adverse effect on the Company’s business, operating results, or financial condition. To mitigate this risk, the Company’s business arrangements with these larger clients are structured as multiple contracts with different statements of work that are specific to a different line of business or service; these contracts have different durations and renewal dates and could have a revenue opportunity above the $100 million aggregate.

To limit the Company’s credit risk with its clients, management performs periodic credit evaluations, maintains allowances for credit losses and may require pre-payment for services from certain clients whose financial stability or payment practices raise concern. Based on currently available information, management does not believe significant credit risk existed as of June 30, 2026 beyond what was already recognized.

Activity in the Company’s allowance for credit losses consists of the following (in thousands):

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