https://www.gov.uk/marriage-abroad/y/spain/uk ; (New Rules)

http://www.hitched.co.uk/chat/forums/t/156627.aspx

They will need a document from the British Embassy staing they are free to marry ie not currently married also their birth certs will have to be translated into Spanish.

Likely documentation you will need:

    Long form birth certificate – notarized and translated into Spanish.
    Valid passport and at least four copies – to be used when you apply for the Empadronmiento, Residencia and file for the marriage.
    Certificate of Marital Status (Certificado de Estado Civil)
    Certificate of No Impediment (Certificado de No Impedimento), which can be obtained from the registrar office of the home country.
    Divorce degrees (Certificados de divorcio) – if applicable
    Spanish Town Hall Registration Certificate (Certificado de Empadronamiento or “Padrón”)
    Extranieria application form – print three copies. Complete the extranjeria form and file it at the national police station. Remember to bring with your passport and a photocopy of it.


Empadronamiento
This is the process of registering yourself as a resident in your province. This is required in some provinces but may not be applicable everywhere. It is best to check beforehand. Fill out the form (it’s the same as the extranjeria form) and take your passport and a photocopy of it along with you. As you are registering yourself as a resident of your province you will need to have an address. This can be a rented address and you will need to show your rental contract.

Step 2: Submitting the paperwork

Bring along a photocopy of your passport along with the necessary documents when you file for your marriage at the local registry office. You will also need one of your two witnesses to accompany you and to bring his/ her passport. The officials will then process your information and register you on their system. The intent to marry is then displayed on the public notice board in their office for 21 days. After 10 days, you can call the office to request an interview date - part of the marriage process.

If you do not speak Spanish it is advisable to either hire a Spanish solicitor or to get someone who speaks Spanish to help you with all of the paperwork so that the process runs smoothly. Also, registry offices can be quite busy and it is usually better to go earlier rather than later in the day.

Step 3: Waiting and going for the interview

Once the 10 days are up, you can call to arrange an appointment for the interview process. Be advised that you may have to wait up to six weeks for the appointment date. At the interview you may be interviewed separately and asked to answer a number of questions to make sure that you are genuine applicants.

Ceremony

A civil marriage can be held in the courts or the Town Hall of residence, performed by the Mayor or a designated councilor. The marriage is effective immediately following the ceremony. After the wedding, it will be registered in the Civil Registry and a certificate stating the date, time and place of the marriage will be issued.

A religious ceremony (or blessing) can be held following the civil ceremony if desired. You should be aware that after a religious ceremony, you have one week to present the church-issued certificate to the nearest civil registry. If you fail to register the marriage will not be recognised.
http://www.expatica.com/es/family/Partners/Getting-Married-in-Spain_13864.html

Hi Got your PM

  If you go to the Gov website

https://www.gov.uk/marriage-abroad/y/spain/uk ; (New Rules)

Go through the questionaire " Are you from the UK " etc on about the forth page you will see a click on for the various forms they are there 



Marriage in Spain

Contact the Embassy of Spain before making any plans to find out about local marriage laws, including what documents you’ll need.

You should also check the travel advice for Spain.

Civil weddings in Spain take place at a town hall, register office or district court. You need to register with the local civil authorities afterwards to get an official marriage certificate if you have a religious wedding.

Check with the civil registry where you’re getting married.

There are certain legal restrictions if neither of you is resident in Spain. If you both live outside Spain, you should check with the civil registry where you’re planning to getting married to find out if this is allowed.
What you need to do

You may be asked to provide a certificate of no impediment (CNI), marital status certificate or both to prove you’re allowed to marry.

You may also need to get a marital status certificate if you’re living with your partner and want to get a ‘pareja de hecho’ (cohabitation registration).

You can normally get a CNI by giving a notice of marriage at your local register office or registrar in the UK. Find your local office or registrar in England and Wales, Scotland or Northern Ireland.

A CNI issued in England, Wales or Northern Ireland is valid for 6 months. A CNI issued in Scotland is valid for 3 months.

They’ll post your notice, and as long as nobody has registered an objection after 7 days, they’ll issue your CNI.
Legalisation and translation

You might need to exchange your UK-issued CNI for one that’s valid in Spain at the nearest embassy or consulate to where you’re getting married.

You should also check if it needs to be:

    ‘legalised’ (certified as genuine) by the FCO
    translated - find a translator abroad, or in the UK through the Institute of Linguists

You should also check with the local authorities to find out if you need to provide legalised and translated copies of any other documents.

Your partner will need to get their own CNI.

Your partner will need to follow the same process and pay the fees to get their own CNI.

The names on all documents you provide must appear exactly as they do on your passports - if not, the authorities may refuse to allow the marriage to go ahead. You may need to provide evidence if the name on your passport is different to your birth certificate (eg marriage certificate or deed poll).
Getting a marital status certificate

In some parts of Spain you may need to to get a ‘marital status certificate’ (‘certificado de estado civil’) instead of, or as well as, a CNI (‘certificado de no impedimento’).

Check with the civil registry where you’re getting married. If you need one, ask a solicitor (‘abogado’) to draw up a declaration for you printed on their headed paper.

If it’s on blank, non-headed paper, they’ll need to give you a separate letter including their contact details, confirming that they’ve drawn up the declaration.

You’ll then need to make an appointment at the consulate to make the declaration and sign the document in front of a consular officer - so don’t sign it beforehand.

Download instructions in English and Spanish on what the declaration needs to include.

Download ‘Marital status declaration instructions in English’ (PDF, 363KB) Download ‘Declaración de estado civil instrucciones en Español’ (PDF, 236KB)

You’ll also need a completed marital status certificate application form, as well as the supporting documents and the fee (see below). These are the same as the ones you need for a CNI.

Download ‘Marital status certificate appointment request form’ (DOC, 53KB)
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Your partner will also need to get a marital status certificate from the consulate and pay the fees if the civil registry have told you that they need one.
Other requirements for Spain

The civil registrar may also ask for confirmation of your addresses for the past 2 years (‘confirmación de domicilio para casarse en España’).

You can get a consular letter with proof of address for marriage from the consulate if you need to provide this.
Fees
Service      Fee
Receiving a notice of marriage      £65
Issuing a CNI, Nulla Osta or equivalent      £65
Issuing any other consular letter or certificate in English      £45
Issuing any other consular letter or certificate in any other language      £70
Administering an oath or making a declaration      £55

You normally have to pay fees for consular services in the local currency - these are shown in the list of consular fees for Spain.

You can pay by cash or credit card, but not by personal cheque.