Calvary Chapel in San Jose was fined last week for ignoring Santa Clara County's mask-wearing rules between November 2020 and June 2021.
The church will appeal, attorney Mariah Gondeiro told the San Jose Mercury News.
Calvary was one of several large California evangelical churches that flouted state and local mask-wearing and social distancing rules designed to prevent the spread of COVID-19 during its deadliest period.
That has led to a tangled web of court rulings and challenges.
Calvary Chapel sued the county, arguing the health orders violated its religious freedom. Various courts have ruled either in favor the church or the county.
The church and its pastors were previously held in contempt of court and fined for violating limits on indoor public gatherings. But a state appellate court reversed those decisions last year, saying that the restrictions on indoor worship services were stricter than for secular activities such as going to grocery stores.
The county continued to seek fines for violations of mask-wearing regulations.