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Company directory · Mountain Ash

Trade and construction companies in Mountain Ash

107 active trade and construction companies registered in Mountain Ash, Mid Glamorgan, by trade.

Trade companies in Mountain Ash in numbers

From the Companies House register and filed balance sheets, as of 1 Oct 2026. The longest-established is Marton (Civil Engineering) Limited, incorporated in 1976.

Companies
107
Active, small or micro accounts
New in the last 12 months
15
14% of the total
Typical net assets
£19K
Median of 80 latest balance sheets
Typical size
2 employees
Median average headcount
Accounts due in the next 3 months
25
Companies House deadlines

Still trading, by year incorporated

Active trade companies in Mountain Ash by year of incorporation0510152017: 5 incorporated (still active)520172018: 1 incorporated (still active)120182019: 11 incorporated (still active)1120192020: 7 incorporated (still active)720202021: 9 incorporated (still active)920212022: 8 incorporated (still active)820222023: 9 incorporated (still active)920232024: 5 incorporated (still active)520242025: 10 incorporated (still active)1020252026: 14 incorporated (still active)142026
Active trade companies in Mountain Ash by year of incorporation0510152017: 5 incorporated (still active)5'172018: 1 incorporated (still active)1'182019: 11 incorporated (still active)11'192020: 7 incorporated (still active)7'202021: 9 incorporated (still active)9'212022: 8 incorporated (still active)8'222023: 9 incorporated (still active)9'232024: 5 incorporated (still active)5'242025: 10 incorporated (still active)10'252026: 14 incorporated (still active)14'26

Companies still active today, by the year they were incorporated; 2026 is the year so far.

Trades in Mountain Ash

Every company on these pages is an active private limited company that files small or micro-entity accounts. Each one has to deliver accounts to Companies House within 9 months of its year end, pay corporation tax 9 months and 1 day after it, and file a CT600 with HMRC within 12 months.

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