Modern oral nicotine products are becoming increasingly popular alternatives to smoking. However, the palatability is largely dependent on added flavorants which may have high chemical diversity with regard to analytical methods development. Furthermore, in clinical studies the measurement of remnant flavors in used products and in saliva during use are often critical for understanding the bioavailability of product components and the overall expected usage timeframe. In this study, a comprehensive strategy was developed and validated to quantify two non-volatile artificial sweeteners plus fourteen volatile flavor components in unused and used smokeless pouch products as well as in saliva for application in support of clinical trials. Analysis of artificial sweeteners required two independent LC-ESI-MS/MS injections using reversed phase and HILIC separation prepared from a single aqueous extract. The volatile flavor components were analyzed by GC-MS using an ethanol-based extract. Each method developed in this study demonstrates analytical characteristics well suited for use in clinical trials in both matrices including low saliva volumes required, low or sub ppm limits of quantification (0.025 µg/mL for sweeteners and < 3 µg/mL for flavorants). The ranges of applicability for the methods are on the order of 100-fold for sweeteners and 400-fold for flavorants (i.e., up to 2.5 µg/mL and 750 µg/mL per saliva sample, respectively). Linearity (R² ≥ 0.996 for sweeteners and ≥ 0.998 for flavorants), accuracy, precision, and specificity all met validation criteria. The development process, methodology, and exemplary validation results will be discussed.