The Submission Project attempts to expand the repertoire available on IMSLP by submitting scans from other high-quality public domain archives. Current sources:
- AUS-CAnl (National Library of Australia)
- B-Br (Bibliothèque royale de Belgique)
- CDN-Tu (University of Toronto)
- CH-Bu (Universitätsbibliothek Basel)
- CH-Bm (Musik-Akademie Basel)
- CH-BEsu (Universitätsbibliothek Bern)
- CH-Gpu (Bibliothèque de Genève)
- CH-Zz (Zentralbibliothek Zürich)
- CZ-Pu (Národní knihovna České republiky)
- D-B (Staatsbibliothek zu Berlin)
- D-Mbs (Bayerische Staatsbibliothek)
- D-Tu (Universität Tübingen)
- F-LYc (Médiathèque Nadia Boulanger)
- F-Pn (Gallica = Bibliothèque nationale de France)
- GB-Lbl (British Library)
- N-Bo (Bergen Offentlige Bibliotek)
- N-Onm (Nasjonalbiblioteket)
- PL-Kj (Uniwersytet Jagielloński)
- SDL (Śląska Biblioteka Cyfrowa)
- US-BEm (University of California, Berkeley)
- US-COu (Ohio State University)
- US-DMu (Duke University)
- US-EU (University of Oregon)
- US-MAu (University of Wisconsin-Madison)
- US-SVu (Mississippi State University)
- US-NYpm (The Morgan Library & Museum)
- US-WC (Baylor University)
- US-Wc (Library of Congress)
