If you’ve spent part of your career outside the UK, your State Pension entitlement may not be as high as you expect. Many British expats miss out on thousands of pounds in retirement simply because they don’t check their National Insurance (NI) record in time. But right now, there’s a limited-time opportunity to top up missing contributions and increase your pension—it could be one of the best financial decisions you make. The deadline to fill in gaps in your NI…