May 21 (Reuters) - AutoZone beat estimates for third-quarter profit on Tuesday, driven by strong demand for automotive parts as more Americans held on to their ageing cars amid higher prices and wait times for newer models.

Quarterly net sales at the auto parts supplier, which competes with Advance Auto Parts and O'Reilly Automotive , rose 3.5% to about $4.24 billion.

Analysts on average were expecting AutoZone to report third-quarter net sales of $4.29 billion.

On an adjusted basis, the company earned $36.69 per share in the quarter ended May 4, compared with analysts estimates of $35.96 per share, according to LSEG data.

However, domestic same-store sales in the quarter remained flat from a year earlier. (Reporting by Nathan Gomes in Bengaluru; Editing by Anil D'Silva)