In general:

• At the Civil Register for the location in which the birth occurred. If the location is unknown, the birth registration is processed at the Register corresponding to the place where the abandoned child was found.

Special cases:

• The responsible Register for registering births while travelling will be the one corresponding to the location in which it occurred (Civil Register of the location where it took place). However, births that occur in Spain, when the registration is processed within the allotted period of time, may be registered at the Civil Register corresponding to the home of record of the legally recognized parent or parents.
• At the Central Civil Registry Office, in the cases mentioned under the heading (BIRTH REGISTRATION APPLICATIONS BEFORE THE CENTRAL CIVIL REGISTRY OFFICE).

Children from marriage:

In this case, a declaration is required from whomever has certain knowledge of the birth, which must be made by the father, the mother, the grandparents, aunts or uncles, cousins or the brothers/sisters-in-law of the new-born, providing the following documentation:

• Medical delivery report (this form is provided by the hospital where the delivery took place).
• D.N.I. (National Identification Card) of the parents and the Family Book (or marriage certificate duly legalised and translated, as appropriate).

Children born out of marriage:

In this case, a declaration is required from the parents, with the father and the mother going to the register in person, providing the following documentation:

• Medical delivery report (this form is provided by the hospital where the delivery took place).
• Their respective D.N.I.s.
• Indication of the mother's marital status.
  • If a prior marriage existed, the legal presumption of paternity must be removed by providing: Marriage certificate (with the corresponding note), and the separation or divorce decree (witnessed).
  • In the case of a de facto separation, two witnesses must accompany the interested party to the Register.

Ministry of Justice, Civil Records Addresses and Phone Numbers

The obligation to declare the birth affects blood relationships up to the fourth degree and relationships by marriage to the second degree; that is, the father or mother, or the grandparents, the aunts or uncles or cousins of the new-born, as well as the brothers/sisters-in-law of the new-born.

Explain the fees structure which is required for obtaining the certificate/document.

Explain the time until which the certificate/document is valid.
e.g. Birth Certificate Valid Forever

Birth registration applications before the Central Civil Registry (PDF. 40 KB)

Download Application form here

Rules

Please explain processing time taken in obtaining the document/certificate.

Videos explaining the procedure or to fill the applications. 
Attach videos using the following tag <&video type="website">video ID|width|height<&/video&> from external websites.
Please remove the "&" inside the tags during implementation.
Website = allocine, blip, dailymotion, facebook, gametrailers, googlevideo, html5, metacafe, myspace, revver, 
sevenload, viddler, vimeo, youku, youtube
width = 560, height = 340, Video ID = Can be obtained from the URL of webpage where the video is displayed.
e.g In the following url "http://www.youtube.com/watch?v=Y0US7oR_t3M" Video ID is "Y0US7oR_t3M". 
	

The period for registering the birth is between 24 hours and 8 days after the birth, after which time, up to 30 calendar days, just cause must be certified and indicated in the registration. After that period, a late birth registration file must be processed before the Registrar or Acting Registrar of the corresponding Civil Register.

Births may also be registered with certifications of register entries issued by foreign Registry Offices, in lieu of the aforementioned file, as long as there is no doubt as to the authenticity of the registered event and its legality under Spanish law.

• Name given to the new-born.
• The date, time and location of the birth. In the case of multiple births, when the exact time is unknown for each new-born, indication shall be given of the order in which they were born, or that this could not be determined.
• Whether the new-born is male or female and the name given.
• The parents, when the relationship is legally recognised.
• The number assigned to the birth or verification file.
• The time of registration.

Birth registration is the register entry, carried out by the person in charge of the Civil Register, which certifies the birth, the date, time of birth and the location in which it took place, the sex and, as appropriate, the relationship of the registered individual. The birth is legally effective from the moment it occurs, but it requires registration in the Civil Register for full recognition.

Therefore, the birth registration is considered the act by which the required individuals report the event to the responsible authorities at the corresponding Civil Registers.

BIRTH REGISTRATION APPLICATIONS BEFORE THE CENTRAL CIVIL REGISTRY OFFICE:

• Direct registration of Spaniards born abroad
• Registration as a Spanish citizen for foreign wives of Spaniards, prior to Law 14/1975, dated 2 May
• Birth registration with registration of Spanish citizenship by option
• Birth registration with registration of Spanish citizenship by reinstatement
• Birth registration with the registration of Spanish citizenship by residency or letter of naturalisation
• Registration of birth and adoption abroad

Please remember that, registering a birth in Spain with the Spanish authorities is a mandatory not an optional procedure.

http://www.mjusticia.gob.es/cs/Satellite/en/1200666550200/Tramite_C/1214483957117/Detalle.html

http://spain.angloinfo.com/healthcare/pregnancy-birth/registration/

http://www.costacalidachronicle.com/articles/115-health-and-beauty-articles/health-and-beauty-articles/308-having-a-baby-in-spain-pregnancy-a-birth--part-two

http://www.tumbit.com/how-to-guides/articles/34-registration-of-a-birth-with-the-spanish-authorities.html

• Firstly, the birth of a child in Spain must be registered at your nearest Registro Civil (Civil register office), within eight days of the childs birth.
• This time period can be extended thirty calendar days if there is a justified reason for the delay. However, it is better to stick to the time frame as a delay may lead to future problems with the Spanish authorities.
• Any Parent or Family Member may register the birth. The registered name must conform to Spanish regulations (regarding compound names) and also ensure that the name will not prove harmful or confusing for the child (Like not being named after your Favourite Character from Star Trek). Whilst this is still an official law, it is only enforced under either extreme or unusual cases.