- a northern-eastern, inland language attested at a relatively late date in the extensive corpus of Celtiberian. This variety, which Jordán Cólera proposed to name northeastern Hispano-Celtic, has long been synonymous with the term Hispano-Celtic and is universally accepted as a Celtic language.
- a language in the north west corner of the peninsula, with a northern and western boundary marked by the Atlantic Ocean, a southern boundary along the river Douro, and an eastern boundary marked by Oviedo, which Jordán Cólera has proposed to call northwestern Hispano-Celtic, where there is a corpus of Latin inscriptions containing isolated words and sentences that are clearly Celtic. 
Western Hispano-Celtic is a term that has been proposed for a putative spectrum of Celtic and para-Celtic dialects, west of an imaginary line running north-south linking Oviedo and Mérida. John T. Koch has added Tartessian as a form of archaic Celtic and Lusitanian as a para-Celtic language, and as part of a language continuum with the other western Iberian Celtic languages.
According to Koch, the Western Celtic varieties of the Iberian Peninsula share with Celtiberian a sufficient core of distinctive features to justify Hispano-Celtic as a term for a linguistic sub-family as opposed to a purely geographical classification.:292 In Naturalis Historia 3.13 (written 77–79 CE), Pliny the Elder states that the Celtici of Baetica (now western Andalusia) descended from the Celtiberians of Lusitania, since they shared common religions, languages, and names for their fortified settlements. According to Koch's theory, the Celtic of the western coastal Iberia, especially in those areas under Phoenician influence, appear to have participated at an early date in linguistic innovations taking part in various parts of the wider Celtic-speaking world as a result of the rapid economic and social development of the 10th-6th centuries BC. Such a situation favored the mixing of dialects and acceptance of some innovative features within the resulting lingua-franca.
As part of the effort to prove the existence of a western Iberian Hispano-Celtic dialect continuum, there have been attempts to differentiate the Vettonian dialect from the neighboring Lusitanian language using the personal names of the Vettones to describe the following sound changes (PIE to Proto-Celtic)::351
- *ō > ā occurs in Enimarus.
- *ō > ū in final syllables is indicated by the suffix of, e. g., Abrunus, Caurunius.
- *ē > ī is attested in the genitive singular Riuei.
- *n̥ > an appears in Argantonius.
- *m̥ > am in names with Amb-.
- *gʷ > b is attested in names such as Bouius, derived from *gʷow- 'cow'.
- *kʷ in PIE *perkʷ-u- 'oak' appears in a lenited form in the name Erguena.
- *p > ɸ > 0 is attested in:
- *perkʷ-u- > ergʷ- in Erguena (see above).
- *plab- > lab- in Laboina.
- *uper- > ur- in Uralus and Urocius.
- However, *p is preserved in Cupiena, a Vettonian name not attested in Lusitania; also in names like Pinara, while *-pl- probably developed into -bl- in names like Ableca.
- Celtiberian language
- Gallaecian language
- Continental Celtic languages
- List of Galician words of Celtic origin
- List of Spanish words of Celtic origin
- Tartessian language
- Celtic languages
- Paleohispanic languages
- Meid, W. Celtiberian Inscriptions (1994). Budapest: Archaeolingua Alapítvány.
- Koch, John T. (2010). "Chapter 9: Paradigm Shift? Interpreting Tartessian as Celtic". In Cunliffe, Barry; Koch, John T. Celtic from the West: Alternative Perspectives from Archaeology, Genetics, Language and Literature. Celtic Studies Publications. Oxford: Oxbow Books. pp. 292–293. ISBN 978-1-84217-410-4. Reissued in 2012 in softcover as ISBN 978-1-84217-475-3.
- Jordán Cólera, Carlos (March 16, 2007). "The Celts in the Iberian Peninsula:Celtiberian" (PDF). e-Keltoi 6: 749–750. Retrieved 16 June 2010.
- Koch, John T. (2005). Celtic Culture: A Historical Encyclopedia. ABC-CLIO. p. 481. ISBN 978-1-85109-440-0.
- Prósper, Blanca María (2002). Lenguas y religiones prerromanas del occidente de la península ibérica. Ediciones Universidad de Salamanca. pp. 422–427. ISBN 84-7800-818-7.
- Wodtko, Dagmar S. (2010). "Chapter 11: The Problem of Lusitanian". In Cunliffe, Barry; Koch, John T. Celtic from the West: Alternative Perspectives from Archaeology, Genetics, Language and Literature. Celtic Studies Publications. Oxford: Oxbow Books. ISBN 978-1-84217-410-4.:360–361 Reissued in 2012 in softcover as ISBN 978-1-84217-475-3.
- Koch, John T. (2009). "Tartessian: Celtic from the South-west at the Dawn of History" (PDF). Acta Palaeohispanica (Zaragosa, Spain: Institución Fernando el Católico) 9: 339–351. ISSN 1578-5386. Retrieved 2010-05-17.. Journal renamed to Palaeohispanica: Revista sobre lenguas y culturas de la Hispania Antigua. This particular work has also been published in book form, and revised: Koch, John T. (2013) . Tartessian: Celtic from the South-west at the Dawn of History. Celtic Studies 13 (2nd ed.). Aberystwyth: David Brown Publishing.
- Pliny the Elder. "3.13". Naturalis Historia.
Celticos a Celtiberis ex Lusitania advenisse manifestum est sacris, lingua, oppidorum vocabulis, quae cognominibus in Baetica distinguntur. Written 77–79 CE. Quoted in Koch (2010), pp. 292–293. The text is also found in online sources: , .
- Lujan, E. (2007). Lambert, P.-Y.; Pinault, G.-J., eds. "L'onomastique des Vettons: analyse linguistique". Gaulois et celtique continental (in French) (Geneva: Librairie Droz.): 245–275.