The retailing giant won approval for the relaxation of a planning condition to allow 24-hour round-the-clock opening every day except Sunday at its store in Fishborne Road East, Chichester.
Planning officers recommended approval, but after hearing local objections, Chichester councillors decided to give permission only for an initial one-year trial period so the local impact can be assessed.
Local residents living near the store led opposition to the store's plans on the grounds that it could lead to an increase in noise and disturbance.
But a noise assessment submitted by Tesco showed noise would be less than the noise from the A27 nearby.
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