<p>New porphyrin dyes employing alkoxysilyl anchoring groups were designed using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) for possible use in dye-sensitized solar cells. The new dyes, named SiA series, demonstrated more favorable charge transfer and enhanced light-harvesting efficiency (LHE) compared with SM315 dye, which utilized the conventional cyanoacrylic acid anchoring unit. Among the designed dyes, the SiA-2 displayed the superior light-harvesting properties as shown by the broadened and bathochromically shifted Q-band, most favorable LHE curve, as well as the highest calculated theoretical maximum photocurrent density (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">\({J}_{\text{SC}}^{\text{max}}\)</EquationSource> </InlineEquation>). The SiA-2 dye also showcased the most enhanced charge transfer properties based on the calculated transferred charges (<InlineEquation ID="IEq2"> <EquationSource Format="TEX">\({q}^{CT}\)</EquationSource> </InlineEquation>), charge-transfer distance (<InlineEquation ID="IEq3"> <EquationSource Format="TEX">\({D}^{CT}\)</EquationSource> </InlineEquation>), and change in dipole moment accompanying intermolecular charge-transfer (<InlineEquation ID="IEq4"> <EquationSource Format="TEX">\({\mu }^{CT}\)</EquationSource> </InlineEquation>). Moreover, the spatial separation distance (<i>r</i>) between the photogenerated hole center and the surface of the TiO₂ semiconductor of SiA-2 suggests a favorable <InlineEquation ID="IEq5"> <EquationSource Format="TEX">\({V}_{\text{OC}}\)</EquationSource> </InlineEquation>. In this series, SiA-2 emerges as the most promising sensitizer due to its favorable overall characteristics.</p>