The disclosure relate to improved oligonucleotide-based compositions and related methods for treating HBV infection in a subject. In some embodiments, the disclosure relates to the development of potent oligonucleotides that produce durable knockdown of HBV surface antigen (HBsAg) expression. The oligonucleotide induce RNA interference (RNAi)-mediated recognition and destruction of mRNA which encodes all forms of HBsAg in hepatocytes. The present disclosure provides oligonucleotides for reducing expression of hepatitis B virus surface antigen (HBsAg) mRNA, the oligonucleotide comprising an antisense strand. In some embodiments, the oligonucleotide further comprises a sense strand, wherein the sense strand forms a duplex region with the antisense strand.