The most important conclusion of this work is that the bottleneck in designing MOFs for overall water splitting lies in the alignment to OER. Our study shows that it is relatively easy to identify a large number of MOFs that have suitable band gaps and band alignment to HER. However, the total number of these MOFs that also have appropriate alignment to OER dropped significantly. Hence, efforts should focus on generating more structures in the region of the chemical design space where OER aligns.