Billion [Say Hello] Billion(빌리언)이 첫 번째 정규앨범 [Say Hello]로 돌아왔다. 총 8곡으로 채워진 이번 앨범에서는 타이틀곡 ‘여보세요’를 포함해 R&B, ROCK, 힙합 등 다양한 장르로 구성하였다.이번 앨범에서는 힘든 일상이 반복되면서 오는 회의감, 불안감 등을 담아내었지만그 사이에도 사랑은 어디에나 존재한다는 뜻을 풀어내었다. 피쳐링진으로는 SOAOA, seoseo, B JYUN., Sonny Zero, FDR (에프디알) 등이 참여하여 앨범의 완성도를 높였다.01. UPSIDE DOWN (Feat. SOAOA) Lyrics by Billion, SOAOAComposed by Billion, SOAOA, FDR (에프디알)Arranged by Billion, FDR (에프디알) 02. Park  (Feat. seoseo) Lyrics by Billion, seoseoComposed by Billion, seoseo, FDR (에프디알)Arranged by FDR (에프디알) 03. 너는 Lyrics by BillionComposed by Billion, wavytrblArranged by wavytrbl 04. sentimental side                                Lyrics by BillionComposed by Billion, FDR (에프디알)Arranged by Billion, FDR (에프디알) 05. 여보세요 (Feat. B JYUN., Sonny Zero) [t]  Lyrics by Billion, B JYUN., Sonny ZeroComposed by Billion, B JYUN., Sonny Zero, st4ndardArranged by st4ndard 06. 습기 (Feat. FDR (에프디알)) Lyrics by Billion, FDR (에프디알)Composed by Billion, FDR (에프디알)Arranged by Billion, FDR (에프디알) 07. 비틀비틀                              Lyrics by BillionComposed by Billion, wavytrblArranged by wavytrbl 08. where I drive Lyrics by BillionComposed by Billion, FDR (에프디알)Arranged by Billion, FDR (에프디알)  Tuning by Billion, FDR (에프디알)Mixed by Billion, FDR (에프디알)Mastered by FDR (에프디알)Recorded by Team Private studioArtwork by 민경진(@minkyeongjin)Presented by Team PrivateExecutive Producer FDR (에프디알)