This strange, seemingly cryptic expression is defined in the RAE’s Diccionario del Español Jurídico como prórroga del contrato de arrendamiento de fincas rústicas o urbanas que se produce cuando, una vez terminado el contrato hecho por tiempo determinado, permanece el arrendatario disfrutando quince días de la cosa arrendada con aquiescencia del arrendador.* In that regard, reconducción refers specifically to prórroga de un arrendamiento (DLE).
Tácita reconducción has often been translated literally as “tacit renewal,” described as “renewal by default” or, perhaps in more idiomatic English, rendered as “automatic renewal (of a lease).” But it should be noted that all of these translations are actually inaccurate, confusing prórroga (“extension”) with renovación (“renewal”). Thus tácita reconducción more appropriately denotes the “automatic extension” of a lease (if, as indicated in the DEJ’s definition above, fifteen days after the contract expires neither party has given notice of termination to the other).
*Código Civil, arts. 1566-1567.
Léxico Jurídico Español-Inglés 
Automatic roll-over e.g. of a letting or lease? That’s what we used in our conveyancing dept. in London and Madrid.
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Hi, Adrian,
“Automatic rollover” is also a good way to describe “tácita reconducción” (although if the tenant doesn’t indicate his desire to terminate the contract, it usually “rolls over” immediately upon expiration, while with “tácita reconducción” there is a fifteen-day period after it expires in which either party may terminate the lease before it is automatically extended. “Rollover” is also often used to denote the automatic extension of a loan or investment, etc.
Saludos from Madrid,
Rebecca
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Hi Rebecca,
Have you ever heard of “holdover tenancy” o “holdingover”? They generally describe what in civil law is known as “tácita reconducción”.
Regards,
Javier
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Hi, Javier,
There is an essential difference between holdover tenancy and “tácita reconducción:” A holdover tenant is “a person who remains in possession of real property after a previous tenancy (especially one under a lease) expires, thus giving rise to a tenancy at sufferance,” i.e., “a tenancy arising when a person who has been in lawful possession of property wrongfully remains as holdover after his or her interest has expired” (Black’s). In this case a holdover tenant is more akin to a “precarista” under Spanish law. In contrast, “tácita reconducción” refers to an automatic renewal of a lease resulting from the presumed acquiescence of both parties to the lease if neither gives notice of termination during the fifteen-day period after the lease has expired, and at no time before or after that fifteen-day period is the tenant considered to have been in wrongful possession.
Saludos desde Madrid,
Rebecca
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