Travelers from the UK will be able to freely enter Spain from today with no restrictions and no coronavirus test

Update. From 00:00 of May 24th, travelers from United Kingdom will be allowed to freely enter Spain for non-essential purposes, such as tourism, and stay in Spain without a visa for a maximum period of 90 days within 6 months. 
From May 24th, travelers from the United Kingdom will NOT need to present negative COVID-19 test certificate (PCR), as long as they have remained in the UK in the last 14 days.
It is mandatory for all residents in the United Kingdom travelling to Spain (including children of all age) to fill in a Health Control Form (FCS). You can download the form in the following link: https://www.spth.gob.es/
The Spanish government has opted to add Japan to the list of countries whose residents will not be subject to coronavirus restrictions when traveling to Spain, including the requirement to present a negative PCR test on arrival.
The current list of countries with no restrictions on travel to Spain is: Israel, Australia, New Zealand, Rwanda, Singapore, South Korea, Thailand and China, as well as the territories of Hong Kong and Macao.

List of countries and areas that require an Active Infection Diagnostic Test for SARS-CoV-2 with a negative result for passengers travelling from them as a requirement to enter Spain.
LIST VALID FROM 12:00AM (MIDNIGHT) ON MAY 24th, 2021 AND WILL BE VALID UNTIL 12:00AM (MIDNIGHT) ON JUNE 6th, 2021