<p>Youth living with chronic pain experience a complex symptom burden, with multiple symptoms that may fluctuate throughout their daily lives. We aimed to explore the daily variability of multiple symptoms including pain, fatigue, cognitive dysfunction, mood, stress, and sleep, in a sample of youth with mixed chronic pain diagnoses. Youth ages 10–17 living with heterogeneous diagnoses of chronic pain lasting 3 or more months with associated functional disability (<i>N</i> = 25) wore wristworn ecological momentary assessment (EMA) monitors for seven days. Three times daily, they provided ratings regarding intensity of pain, fatigue, cognitive dysfunction (perceived clarity and speed of thought), mood, and stress. They also rated sleep daily. Youth also completed a series of standard recall questionnaires corresponding to domains assessed in the EMA ratings. Descriptive statistics, intra-class correlation coefficients, and multilevel models were used to describe the EMA ratings, assess within- and between-person variability, and explore diurnal patterns of ratings. Both trait-like and state-like patterns were observed in the EMA ratings. Diurnal patterns were also observed, with less fatigue (<i>B</i>_{<i>EVENING</i>} = -0.85, <i>p</i> = .003) reported at day’s end. At the within-person level, higher daily pain intensity was associated with worse same-day fatigue (<i>B</i> = 0.34, <i>p</i> &lt; .001) and mood (<i>B</i> = 0.41, <i>p</i> &lt; .001). Conclusions: Findings highlight the complex symptom burden and nuanced daily experiences of youth living with chronic pain, and may lead toward more precise, time-sensitive interventions.</p>