Photoredox catalysis has emerged as a privileged reaction platform for accessing novel reactivity, unlocking a wealth of novel retrosynthetic disconnections. Upon light excitation, the generated photoactive species can interact directly with a substrate or couple with catalytic cycles of transition metals, facilitating challenging mechanistic steps through photoinduced electron-and energytransfer processes. Within this context, the scope of photoactive species has largely been dominated by Ru and Ir polypyridyl complexes, which feature large extinction coefficients (ε), longlived excited states, and large redox windows of operation due to the dual reducing and oxidizing nature of their excited states. It is well known that the modus operandi of these privileged photocatalyst scaffolds involves initial excitation to access a S0 → S1 transition enabled by metal-to-ligand charge transfer (MLCT). This is generally followed by a spin-forbidden intersystem crossing (ISC) to the salient triplet state (T1), facilitated by spin-orbit coupling (SOC) at the heavy-atom center. For the majority of the common photocatalysts based on Ir and Ru however, accessing the S1 excited states requires highly energetic blue or near-UV light, which features low penetration through reaction media and living tissue, higher scattering of shorter wavelengths (proportional to λ -4 ) , and can lead to unwanted side reactivity with chromophore-bearing moieties. All these issues limit the innate sustainability and scalability of such methods. To bypass the aforementioned limitations, the last four years have witnessed a flurry of research activity aimed towards translating the arsenal of photoredox catalysis to lower-energy wavelengths, specifically in the deep red (DR) and near-infrared (NIR) regions of the electromagnetic spectrum. Breaking ground in this area could have applications across a range of fields, such as (batchscalable) photocatalysis, photon up-conversion, and photodynamic therapy, owing to the high penetration of red light through living tissue. Organic dyes, dimethoxyquinacridinium species, (aza)porphyrinoids, and cyanines are some examples of red light-active photocatalysts that have recently emerged and found applications in synthesis (Figure ). Notably, a seminal report by Rovis and coworkers demonstrated that Os-based complexes ([Os(tpy)2] 2+ ) are active photocatalysts in the 660-800 nm range (Figure ), due to their ability to undergo direct spin-forbidden S0 → T1 excitation facilitated by the large spin-orbit coupling (SOC) at Os. The authors remark that this photophysical modality circumvents energy losses associated with ISC, which usually reach around ~25% of the absorbed energy for commonly employed Ru and Ir bipyridyl complexes. Subsequently, several reports have shown that analogous Os polypyridyl complexes are competent red-light photocatalysts in metallaphotoredox-catalyzed C-N couplings, Cu-catalyzed difunctionalization of alkenes, light-controlled Ru-catalyzed olefin metathesis, and protein proximity labeling in tumor tissue cells. However, despite an energetically efficient excitation, the Os complexes present low molar absorptivity in the NIR (415 M -1 cm -1 at 740 nm), potentially requiring higher light intensities to promote desired reactivity. Furthermore, the most reducing Os(L)2 and Os(L)3 complexes capable of absorbing red light feature modest excited-state redox potentials (E°(Os III/II* ) of ca. -1.3 V vs Fc +/0 , 36 limiting their ability to reductively activate substrates or organometallic species with more negative Ered values.