A method of estimating crosstalk delay for an integrated circuit design flow includes steps of: (a) receiving an integrated circuit design; (b) selecting a list of blocks for which crosstalk delay is to be estimated from the integrated circuit design; (c) selecting one of a plurality of crosstalk delay estimation algorithms or no crosstalk delay estimation algorithm for each block in the list of blocks; (d) performing the selected one of the plurality of crosstalk delay estimation algorithms or no crosstalk delay estimation algorithm to estimate a delay for each block in the list of blocks; and (e) generating as output the estimated delay for each block in the list of blocks.