We present a reduction and analysis of the James Webb Space Telescope (JWST) SMACS 0723 field to conduct a search for ultra-high-redshift galaxies (9 < 𝑧 < 12) present within the Epoch of Reionization. We use a combination of photometric redshifts and spectral energy distribution (SED) modelling-based selection criteria to optimise sample completeness while minimising contamination. We find four 𝑧 > 9 candidate galaxies which have not previously been identified, with one object at 𝑧 = 11.5, and another which is possibly a close pair of galaxies. These sources are fairly bright with 𝑚 277 ∼ 26 − 28. A significant fraction of these sources show evidence for Balmer-breaks or extreme emission lines from H𝛽 and [OIII], demonstrating that the stellar populations could be quite advanced in age or very young depending on the exact cause of the F444W excess. We discuss the stellar masses and resolved structures of these early galaxies and find that the Sérsic indices reveal a mixture of light concentration levels, but that the sizes of all our systems are exceptionally small in general with < 0.5 kpc. These systems have stellar masses M * ∼ 10 9.5 M with our 𝑧 ∼ 11.5 candidate a dwarf galaxy with a stellar mass M * ∼ 10 7.9 M These candidate ultra high-redshift galaxies are excellent targets for future NIRSpec observations to understand better their physical nature.

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