The Pensions Act 2008 lays the legal basis for all pension-related operations in the UK, and its implementation is overseen by the Department for Work and Pensions. Over the past few years, there have been a few changes made to the duties that employers have with regards to providing a pension scheme, and also to the details of basic state pensions. For general information on pensions, please refer to the following sites:
Department for Work and Pensions
Pensions Regulator
Online Pension Planner

Workplace Pensions

Workplace pensions are in place to ensure that a regular amount is paid into an employee's pension pot. These are arranged by employers and minimum contribution levels apply, which are calculated based on the employee's qualifying earnings.

As of 2016, there are 2 pension types available to UK workers in addition to government state pensions:

Pension Types
Workplace Pensions
Workplace Pension Calculator
Minimum Workplace Pension Contributions
Defined Contribution Schemes
Defined Benefit Schemes

Automatic Enrolment into Workplace Pension Schemes

The Pensions Act 2008 requires that all UK employers enrol certain staff members into a pension scheme. The process is known as Automatic Enrolment and applies to companies that have at least one employee, but also to individuals who employ staff directly, such as housekeepers, cleaners, personal assistants, nannies, etc.

Eligibility criteria includes an annual salary of over £10,000 (or pro rata) and being between 22 and 74 years old. Employers must find out their staging date (the date enrolment becomes effective), as this date is being gradually implemented and differs depending on whether their employees are paid via PAYE or other methods. Employers who overlook their duty regarding automatic pension enrolments may be issued penalties for non-compliance. The minimum penalty is £400 and can be as high as £50,000 for organisations who fail to comply.
Guidance on Automatic Enrolment
Automatic Enrolment Pension Duties Checker
Find Your Staging Date

Salary Sacrifice Pension Schemes and Tax Incentives

In some cases, it is possible to forfeit part of a salary in order to receive a higher pension amount. Salary sacrifice pension schemes must be arranged directly with the employer after weighing the pros and cons. It is also possible to use incentive awards (such as bonuses or other cash rewards) towards a salary sacrifice scheme.

In most cases, changes to an employee's overall salary as a result of a salary sacrifice scheme will not affect their income tax and National Insurance Contribution liability. This means that the amount contributed in lieu of salary is considered an employer contribution that is not subject to tax on the employee.
Salary Sacrifice Schemes
Guide to salary sacrifice schemes and their effect on PAYE
Salary sacrifice and contributions to pension schemes
Income tax effects of salary sacrifice schemes

State Pensions

A basic state pension is available to anyone who reaches pension age and has paid or been credited National Insurance contributions during their working life. The maximum state pension amount increases on an annual basis and as of 2016 it was set at £119.30 / week. State pension claims can be made online, on paper, or over the phone, both from within the UK and from abroad.

New pension rules came into effect for those who reached state pension age on 6 April 2016 or after that date. The maximum allowance is £155.65 / week, which is paid in arrears every 4 weeks.
General information about state pensions
Claiming basic state pension
New State Pension

Personal Pensions

UK workers may choose to arrange a personal pension plan in addition to their workplace pension and to any state pension entitlements. The objective of a personal pension plan is to increase the overall amount paid into a pension pot. These contributions are invested into a pension fund, and in many cases they are eligible for tax relief.

Personal pensions are available to employed workers, self-employed individuals, and those who are not in work.

There are various types of personal pensions available, including:

General information on personal pensions
Choosing a personal pension
Details on self-invested personal pension plans
Details on stakeholder pensions