The key to a firm’s survival, profitability, and growth in a highly competitive marketing environment is its ability to identify and satisfy unfulfilled consumer needs better and sooner than the competitor. It has become imperative for business entities to strategically think about how to attract and subsequently retain customers. The study therefore seeks to examine the impact of relationship marketing strategies on sustained competitive advantage. Empirically, the study establishes that within the Ghanaian context banks can equally gain sustained competitive advantage through relationship marketing strategies. Purposive sampling technique was used to select the respondents for the study since the study only targeted relationship staff of the respective banks. It was noticed from the study that, communication, bonding, and commitment perfectly established positive significant effect on relationship marketing and sustained competitive advantage. Interestingly communication was found to be the highest contributor to sustained competitive advantage in the Ghanaian banking industry, followed by commitment and conflict handling in that order. This implies that banks that intending to attain sustained competitive advantage should strategically employ the entire integrated marketing communication elements and communicate it to the target audience in the timely and accurate manner. The banks must resolve conflicts in a manner that will boost the confidence of the customer after the conflict resolution. This work has deepened the understanding of bank marketing in Ghana by proving that banks can achieve sustained competitive advantage by investing more and more in relationship marketing practice mostly in communication, commitment and conflict handling.