The disclosed computer-implemented method for delayed allocation in cluster storage may include (i) delegating, to a node attached to a storage cluster including one or more storage devices that include a group of allocation units, a subset of allocation units on the storage cluster to be held as a delayed allocation pool, (ii) receiving, from the node, a request to allocate allocation units on the storage cluster, (iii) deducting the number of allocation units from available allocation units in the delayed allocation pool, (iv) satisfying the allocation request by allocating allocation units not in the delayed allocation pool before allocating allocation units included in the delayed allocation pool, and (v) recalculating, based on the number of allocation units in the delayed allocation pool used to satisfy the allocation request, the number of available allocation units in the delayed allocation pool. Various other methods, systems, and computer-readable media are also disclosed.