We tested the sensitivity of early life stages and the potential for geoduck clams to display acclimatization to ocean acidification through a series of  repeat exposure experiments.  First, we exposed larval geoducks to ambient (~8.0) and low pH (~7.4) for 10 days and found that larval mortality is decreased and shell size increased in low pH conditions. Second, we exposed juvenile geoduck to ambient (~8.0), low (~7.4) and lower (~7.0) pH for 23 days, placed them in ambient common garden for several months, then re-exposed them to ambient (~8.0) pH and low pH (~7.4) for another 23 days. In geoduck juveniles there was a size benefit of preconditioning to low pH. Juvenile growth initially declined at pH ~7.4 and 7.0 in the first exposure, but when replaced in the ambient conditions, the initial exposure to low pH resulted in compensatory growth, such that the juveniles grew larger. Growth in the pre-exposed juveniles was also more resistant to low pH in the second exposure. The role of DNA methylation as a mechanism of environmental memory was tested using reduced representation bisulfite sequencing. This suggests that acclimatization to OA can result in benefits to geoduck growth, with exposure memory that is potentially linked to epigenetic mechanisms such as DNA methylation.