Kaarst - Krefeld
- Kaarst (see Specials: Handschriftencensus Rheinland, vol. 1) Kath. parish St. Martin
- Kaldenkirchen (Nettetal-) (see Specials: Manuscript Census Rhineland, vol. 1) Cath. parish St. Clemens
- Kalkar (see Specials: Manuscript Census Rhineland, vol. 1) Cath. parish St. Nikolai City Archives
- Kamp-Lintfort (see Specials: Handschriftencensus Rheinland, vol. 1)Ordensmuseum (European meeting place at Kamp Monastery) Kath. parish Liebfrauen-Abteikirche
- Karlsruhe State Library
- Kassel University Library - State Library and Murhard Library
- Kempen (see Specials: Handschriftencensus Rheinland, vol. 1) Kath. Propsteigemeinde St. Mariae Geburt
- KemptenChurch librarynear St. Mang
- Kerpen (see Specials: Manuscript Census Rhineland, Vol. 1) Cath. parish St. Martinus Kerpen-Sindorf: Cath. parish St. Mary Queen
- Kevelaer (see Specials: Manuscript Census Rhineland, Vol. 1) Oratory
- Kiel University Library
- Kleve (see Specials: Manuscript Census Rhineland, Vol. 1) Museum Haus Koekkoek City Archives
- Koblenz Görres-Gymnasium (Deposit in Landeshauptarchiv) Landeshauptarchiv Rheinische Landesbibliothek, Stadtarchiv, Stadtbibliothek (see Specials: Databases, Manuscript Census RLP)
- Cologne Cathedral and Diocesan ArchivesArchbishop's Diocesan and Cathedral LibraryHistorical Archive of the CityLibrary of the Hochschule für Musik (see Specials: Manuscript Census Rhineland, Vol. 1) Archbishop's Diocesan Museum, Historical Archive of the Archdiocese, Kath. Parish of St. Kunibert, Church Association of the Protestant Parishes, Protestant Library, Schnütgen Museum, University and City Library, Wallraf-Richartz Museum / Ludwig Collection (see Specials: Manuscript Census Rhineland, Vol. 2)
- Königswinter (see Specials: Manuscript Census Rhineland, vol. 2) Cath. parish St. Remigius
- Kranenburg (see Specials: Manuscript Census Rhineland, Vol. 2) Cath. parish of St. Peter and Paul
- Krefeld (see Specials: Manuscript Census Rhineland, Vol. 2) Gymnasium am Moltkeplatz Private property