Is London a Good BQ Course?

Published October 3, 2026 · Estimates, updated each registration cycle

Short answer: as a course, London is one of the fastest places in the world to run a Boston qualifier. As a plan, it is one of the hardest, because getting a start line place is far less certain than running the time. The 2027 TCS London Marathon is the first two day edition, with about 45,000 runners on Saturday, April 24 and 55,000 on Sunday, April 25, both on the same route from Greenwich to Westminster. Either day falls inside the qualifying window for the 2028 Boston Marathon, and the course is a certified World Marathon Major, so a London time counts at full value on a Boston application.

What the course looks like

The race starts on the Blackheath plateau and finishes on The Mall in front of Buckingham Palace. In between it runs through Charlton and Woolwich, past the Cutty Sark at about mile 6, over Tower Bridge just before halfway, out and around the Isle of Dogs and Canary Wharf, then back west along the Embankment past the Houses of Parliament. Course guides put the net drop at about 35 meters, roughly 115 feet, with total climb of only around 127 meters. The biggest downhill comes early, off Blackheath between about kilometers 5 and 7, and that is where many runners bank seconds they later pay back. The net drop is nowhere near the 1,500 foot line where Boston starts adding time, so the downhill adjustment does not touch a London result. For the courses it does affect, see which marathons are too downhill.

Weather, crowds and the GPS problem

Late April in London usually means cool mornings in the 40s and 50s, which is close to ideal. It is not guaranteed: some editions have been warm enough to wreck goal times, and a mid morning start leaves less margin than an early American race. The second real cost is congestion. With tens of thousands of runners per day on narrow streets around Greenwich and Canary Wharf, weaving adds distance. Tall buildings at Canary Wharf also scramble GPS watches, so many runners see pace jump around in the late teens. Run that stretch by effort and the mile markers, not the watch, and aim for the blue line where the crowd allows. For how heat has shaped past Boston cutoffs, see weather and cutoffs.

The real obstacle: getting a place

The public ballot for 2027 drew a record 1,338,544 entries for about 100,000 places, and the results went out on July 9, 2026, so that door is closed for this cycle. The remaining routes are charity places, which carry a fundraising pledge, Good For Age and championship entries, which are meant for UK based runners, and travel packages sold through official international tour operators. For a runner in the United States, that usually means a charity or a tour package. If you do not already hold a London place, do not build your 2028 Boston plan around it. The access gap between the majors is laid out in Boston vs London entry.

The number to actually aim at

Qualifying is the floor, not the target. The 2027 race cut at 5:17 under the standard, after 4:34 for 2026. The 2028 cutoff is not known, so any target is a planning number, not a forecast. Take a 45 year old woman, standard 3:45:00. With a planning buffer of 6:00, above both of the last two cutoffs, she would aim for 3:39:00. That is 8:21 per mile or 5:11 per kilometer, reaching halfway, just past Tower Bridge, in about 1:49:30 on an even split. Because the early miles are the fastest part of the course, hold back to goal pace through Charlton rather than chasing the free downhill. Tiers for every age group are in what time you need for Boston 2028.

A note on timing

London 2027 comes six days after Boston on April 19, 2027. If you already hold a Boston 2027 bib, doubling up is a recovery run, not a qualifier. If you are chasing 2028, the April date is early enough to leave a fall backup race inside the 2028 qualifying window. For a flat European alternative with a far easier entry, compare is Berlin a good BQ course.

Verdict

London is a good BQ course: certified, fast, only gently downhill and run in usually cool spring weather, with crowd support few races can match. Its costs are congestion, unreliable GPS in Canary Wharf and, above all, the difficulty of getting in. If you have a place, it is a strong day to bank a buffer. Before you set a goal, put your age, gender and target time into the cutoff predictor to see how that buffer would have fared against every real Boston cutoff since 2014.