# timestamp The block’s header timestamp (Unix epoch seconds), or `nil` if the source did not provide one. ``` let timestamp: Date? ``` ## Discussion Remote tips returned from [`bestTip()`](/documentation/BitcoinKernel/EsploraBlockSource/bestTip()) have `timestamp == nil` — the tip endpoint only returns height and hash. Local tips constructed from a kernel [`BlockTreeEntry`](/documentation/BitcoinKernel/BlockTreeEntry) always carry the timestamp from the stored 80-byte header.