Within areas that are subdivided noncontiguously, annexation can take place whereby a lower-tier municipality can annex territory under the jurisdiction of a higher-tier municipality, or tiers do not exist a local municipality can annex territory from another local municipality. The rules that govern municipal annexations in absorption of neighbouring territory vary by country. For example, in the United States, incorporated cities and towns often expand their boundaries by annexing unincorporated land adjacent to them. Municipalities can also entirely annex and be entirely annexed by other municipalities, though this is less common in the United States. Laws governing the ability and the extent municipalities can expand in this fashion are defined by the individual states' constitutions.

Annexation of neighbouring communities occurs in Canada. The City of Calgary, for example, has in the past annexed the communities of Bridgeland, Riverside, Sunnyside, Hillhurst, Hunter, Hubalta, Ogden, Forest Lawn, Midnapore, Shepard, Montgomery, and Bowness. Another example of an annexation in Canada occurred when the city of London, Ontario annexed Wortley Village in 1890.