Chaplow joined Burnley at the age of eight,[2] before earning a scholarship at the club in 2001 as part of the YTS Apprenticeships, turning down offers from Blackburn Rovers and Manchester City.
[6][10] Despite this, Chaplow continued to a handful of first-team appearances at the start of the season, playing in the midfielder position, and scored his first goal for the club on 30 August 2003, in a 1–0 win over Crewe Alexandra.
[22] Ahead of the 2004–05 season, Chaplow was subject of a transfer move throughout the summer, with Blackburn Rovers and Leeds United.
[26][27] However, Chaplow was soon sidelined for several months with a cartilage trouble, which he sustained and substituted in the first half, in a 3–0 defeat to Queens Park Rangers on 30 October 2004.
[28] After a month out, he made his first team return from injury on 18 December 2004, coming on as a second-half substitute, in a 2–1 loss against Sunderland.
[29] In the January transfer window, Chaplow was linked with a move to Premier League side West Brom Albion and had a bid rejected from Burnley shortly after.
[32] Chaplow joined West Bromwich Albion for a fee of £1.5 million on transfer deadline day in January 2005.
He won a penalty soon after coming on as a late substitute, enabling Robert Earnshaw to complete his hat-trick from the spot.
On 9 January 2008, Chaplow signed for Championship team Preston North End on a three-year contract for £800,000 with a further £550,000 payable based on various performance-related criteria.
[51] Three days after signing for the club, Chaplow made his Preston North End debut, making his first start and played for 75 minutes, in a 1–0 win over Watford.
With the club facing financial troubles, Chaplow was among eight players to place on a transfer list by Manager Darren Ferguson.
[69] Having made no appearances for Preston North End in the 2010–11 season, Chaplow joined Southampton once again for an initial one month's loan on 30 September 2010.
[71] Three days later after signing for the club, Chaplow made his Southampton debut for the second time, coming on as a second-half substitute and subsequently picked up a yellow card, in a 2–0 win over AFC Bournemouth.
[78] Later in the 2010–11 season, Chaplow helped the club secure promotion to The Championship after a two years absence, as he made thirty–five appearances and scoring five times in all competitions.
[83][84] However, in a match against Bristol City on 26 November 2011, Chaplow suffered a knee injury early in the first half and was substituted, in a 2–0 loss and was subsequently out for months.
[85] Despite making his return, Chaplow continued to be dropped from the first team on three occasions and saw Southampton promoted to the Premier League after a seven years absence.
[88] It wasn't until on 28 August 2012 when he made his first appearance of the season, setting up one of the goals, in a 4–1 win over Stevenage in the second round of League Cup.
[89] On 29 September 2012, Chaplow made his first Premier League appearance in six years, coming on as a late substitute, in a 3–1 loss against Everton.
[91] It wasn't until on 16 January 2013 when he made his first team return in months, coming on a second-half substitute, in a 2–2 draw against Chelsea.
[111] On 20 February 2015, Chaplow signed on loan for a month at Ipswich Town, with an agreement that he could stay until the end of the season.
[112][113] Chaplow made his Ipswich Town debut four days later, where he came on as a second-half substitute, in a 4–2 win over Birmingham City.
[121] Weeks later, he sidelined for months and it wasn't until on 19 December 2015, where he returned since being absent in October as a late substitute, in a 3–3 draw against Burton Albion.
[131] Two days after signing for the club, Chaplow made his Orange County Blues debut, coming on as a second-half substitute, in a 2–0 win over LA Galaxy II.
[134] After serving a two match suspension, Chaplow returned to the first team and then on 25 September 2016 against Colorado Springs Switchbacks, he set up two goals, in a 4–0 win.
[148] In October 2005 he captained the England under-20 side to a 2–2 draw with the Netherlands, in a match played at his former club Burnley's Turf Moor ground.
[150] On 9 November 2021, Orange County removed the interim tag and made Chaplow the permanent head coach.
[151] Chaplow would lead OCSC to finish second in the Pacific Division, and advance to the USL Championship Final defeating Tampa Bay Rowdies at home, 3–1 in regulation.
[153] Growing up, Chaplow attended Mount Carmel Roman Catholic High School[4] and supported Burnley.