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<p>Meteoric <span class="inline-formula">¹⁰</span>Be (<span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span>) concentrations in soil profiles have great potential as a geochronometer and a tracer of Earth surface processes, particularly in fine-grained soils lacking quartz that would preclude the use of in situ produced <span class="inline-formula">¹⁰</span>Be (<span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_{in situ}</span>). One prerequisite for using this technique for accurately calculating rates and dates is constraining the delivery, or flux, of <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span> to a site. However, few studies to date have quantified long-term (i.e., millennial) delivery rates, and none have determined a delivery rate for an eroding soil. In this study, we compared existing concentrations of <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_{in situ}</span> with new measurements of <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span> in eroding soils sampled from the same depth profiles to calibrate a long-term <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span> delivery rate. We did so on the Pinedale (<span class="inline-formula">∼</span> 21–25 kyr) and Bull Lake (<span class="inline-formula">∼</span> 140 kyr) glacial moraines at Fremont Lake, Wyoming (USA), where age, grain sizes, weathering indices, and soil properties are known, as are erosion and denudation rates calculated from <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_{in situ}</span>. After ensuring sufficient beryllium retention in each profile, solving for the delivery rate of <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span>, and normalizing for paleomagnetic and solar intensity variations over the Holocene, we calculate <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span> fluxes of 1.46 (<span class="inline-formula">±</span>0.20) <span class="inline-formula">×</span> 10<span class="inline-formula">⁶</span> atoms cm<span class="inline-formula">⁻²</span> yr<span class="inline-formula">⁻¹</span> and 1.30 (<span class="inline-formula">±</span>0.48) <span class="inline-formula">×</span> 10<span class="inline-formula">⁶</span> atoms cm<span class="inline-formula">⁻²</span> yr<span class="inline-formula">⁻¹</span> to the Pinedale and Bull Lake moraines, respectively, and compare these values to two widely used <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span> delivery rate estimation methods that substantially differ for this site. Accurately estimating the <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span> flux using these methods requires a consideration of spatial scale and temporally varying parameters (i.e., paleomagnetic field intensity, solar modulation) to ensure the most realistic estimates of <span class="inline-formula">¹⁰</span>Be<span class="inline-formula">_met</span>-derived erosion rates in future studies.</p>