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tokens: it could be due to tidal stripping of the outer disk, or to “classical” accretion of dwarfs. The recent discovery of a substantial population of low-mass dwarfs associated with the Large Magellanic Cloud (Koposov et al. 2015 ; Drlica-Wagner et al. 2016 ) strengthens the latter scenario. The Clouds are not the only dwarfs with known satellites: dwarf galaxy companions have been found around various Magellanic analogs (Martínez-Delgado et al. 2012 ; MADCASH Survey: Carlin et al. 2016 ). A reasonable expectation is that a subset of these satellites will be tidally destroyed and accreted by their host halos, providing additional motivation to search for accreted stellar halos in dwarf galaxies. Stellar halos of galaxies are predicted and observed to be of very low surface brightness. This makes it challenging to study their presence quantitatively through diffuse light. Instead, the most tractable way to search for stellar halos is through deep, wide-field imaging now available on a number of large telescopes located at excellent sites. The isolated Local Group dwarf irregular IC 1613 is a good candidate to search for a stellar halo. It is a gas-rich, low-luminosity galaxy with an absolute magnitude of M V = −15.2 (McConnachie 2012 ), corresponding to a stellar mass of ∼10 8 M ⊙ . Its high Galactic latitude implies low foreground extinction, while it is near enough (725 ± 17 kpc; Hatt et al. 2017 ) that its bright stars are accessible in a reasonable exposure time from the ground. IC 1613 has been continuously forming stars throughout its lifetime, and hosts stars ranging from [Fe/H] ∼ −2 to −0.8 (Cole et al. 1999 ; Skillman et al. 2003 , 2014 ; Bernard et al. 2007 ; Weisz et al. 2014 ). A variety of studies sensitive to different stellar populations at different radii have found that the young stars are more centrally concentrated than the intermediate-age and old stars (Cole et al. 1999 ; Albert et al. 2000 ; Borissova et al. 2000 ; Skillman et al. 2003 ; Sibbons et al. 2015 ; McQuinn et al. 2017 ); though, there has been no definitive detection of a stellar halo as distinct from an extension of the primary body of IC 1613. The aim of this paper is to map IC 1613 with Subaru/Hyper Suprime-Cam (HSC) over a wider area and to fainter magnitudes than previous studies, generating the most sensitive map of its outer structure to date. The paper is organized as follows. The observations and information about how the data were reduced is presented in Section 2 . Section 3 describes the method of selecting different stellar tracers from the galaxy and goes on to explain the various analysis done with them. Section 4 compares our results with past works and places this project in a theoretical context. The conclusions are summarized in Section 5 . 2. Observations and Data Reduction IC 1613 was observed on 2015 October 16, with the HSC (Miyazaki et al. 2012 ) on the Subaru Telescope. The large aperture (8.2 m) of the telescope, along with the 15 field