When should I return a sample?

UK: Return your sample the same day it was taken. In the UK, use the prepaid envelope and any Royal Mail post box (no stamp needed). If day 3 falls on a Saturday, use a post box with Saturday collection or arrange a DHL pickup. If it falls on a Sunday, keep the sample at room temperature out of direct sunlight and post it first thing Monday (in Ireland, schedule the earliest DHL slot).

IRE: Return your sample the same day it was taken. In Ireland, arrange DHL collection before collecting your sample (online or phone 0818 725 725), aiming for same-day collection; your instructions and waybill number are emailed to you and printed on the returns envelope. If day 3 falls on a Saturday, use a post box with Saturday collection or arrange a DHL pickup. If it falls on a Sunday, keep the sample at room temperature out of direct sunlight and post it first thing Monday (in Ireland, schedule the earliest DHL slot).